diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/DroidFish.java b/DroidFishApp/src/main/java/org/petero/droidfish/DroidFish.java
index 8506bf6..ebcf892 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/DroidFish.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/DroidFish.java
@@ -48,6 +48,7 @@ import org.petero.droidfish.activities.util.PGNFile;
 import org.petero.droidfish.activities.util.PGNFile.GameInfo;
 import org.petero.droidfish.activities.Preferences;
 import org.petero.droidfish.book.BookOptions;
+import org.petero.droidfish.engine.DroidComputerPlayer.EloData;
 import org.petero.droidfish.engine.EngineUtil;
 import org.petero.droidfish.engine.UCIOptions;
 import org.petero.droidfish.gamelogic.DroidChessController;
@@ -136,6 +137,7 @@ import android.view.View.OnTouchListener;
 import android.view.WindowManager;
 import android.webkit.WebView;
 import android.widget.ArrayAdapter;
+import android.widget.CheckBox;
 import android.widget.EditText;
 import android.widget.ImageButton;
 import android.widget.ImageView.ScaleType;
@@ -1094,8 +1096,7 @@ public class DroidFish extends Activity
         mEcoHints = getIntSetting("ecoHints", ECO_HINTS_AUTO);
 
         String engine = settings.getString("engine", "stockfish");
-        int strength = settings.getInt("strength", 1000);
-        setEngineStrength(engine, strength);
+        setEngine(engine);
 
         mPonderMode = settings.getBoolean("ponderMode", false);
         if (!mPonderMode)
@@ -1308,16 +1309,16 @@ public class DroidFish extends Activity
             getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
     }
 
-    private void setEngineStrength(String engine, int strength) {
+    private void setEngine(String engine) {
         if (!storageAvailable()) {
             if (!"stockfish".equals(engine) && !"cuckoochess".equals(engine))
                 engine = "stockfish";
         }
-        ctrl.setEngineStrength(engine, strength);
-        setEngineTitle(engine, strength);
+        ctrl.setEngine(engine);
+        setEngineTitle(engine, ctrl.eloData().getEloToUse());
     }
 
-    private void setEngineTitle(String engine, int strength) {
+    private void setEngineTitle(String engine, int elo) {
         String eName = "";
         if (EngineUtil.isOpenExchangeEngine(engine)) {
             String engineFileName = new File(engine).getName();
@@ -1336,10 +1337,10 @@ public class DroidFish extends Activity
             eName = getString("cuckoochess".equals(engine) ?
                               R.string.cuckoochess_engine :
                               R.string.stockfish_engine);
-            boolean analysis = (ctrl != null) && ctrl.analysisMode();
-            if ((strength < 1000) && !analysis)
-                eName = String.format(Locale.US, "%s: %d%%", eName, strength / 10);
         }
+        if (ctrl != null && !ctrl.analysisMode())
+            if (elo != Integer.MAX_VALUE)
+                eName = String.format(Locale.US, "%s: %d", eName, elo);
         engineTitleText.setText(eName);
     }
 
@@ -1363,10 +1364,9 @@ public class DroidFish extends Activity
     }
 
     @Override
-    public void updateEngineTitle() {
+    public void updateEngineTitle(int elo) {
         String engine = settings.getString("engine", "stockfish");
-        int strength = settings.getInt("strength", 1000);
-        setEngineTitle(engine, strength);
+        setEngineTitle(engine, elo);
     }
 
     @Override
@@ -1433,31 +1433,34 @@ public class DroidFish extends Activity
     }
 
     private class DrawerItem {
-        int id;
-        int itemId; // Item string resource id
+        DrawerItemId id;
+        private int resId; // Item string resource id
 
-        DrawerItem(int id, int itemId) {
+        DrawerItem(DrawerItemId id, int resId) {
             this.id = id;
-            this.itemId = itemId;
+            this.resId = resId;
         }
 
         @Override
         public String toString() {
-            return getString(itemId);
+            return getString(resId);
         }
     }
 
-    static private final int ITEM_NEW_GAME = 0;
-    static private final int ITEM_EDIT_BOARD = 1;
-    static private final int ITEM_SETTINGS = 2;
-    static private final int ITEM_FILE_MENU = 3;
-    static private final int ITEM_RESIGN = 4;
-    static private final int ITEM_FORCE_MOVE = 5;
-    static private final int ITEM_DRAW = 6;
-    static private final int ITEM_SELECT_BOOK = 7;
-    static private final int ITEM_MANAGE_ENGINES = 8;
-    static private final int ITEM_SET_COLOR_THEME = 9;
-    static private final int ITEM_ABOUT = 10;
+    private enum DrawerItemId {
+        NEW_GAME,
+        SET_STRENGTH,
+        EDIT_BOARD,
+        SETTINGS,
+        FILE_MENU,
+        RESIGN,
+        FORCE_MOVE,
+        DRAW,
+        SELECT_BOOK,
+        MANAGE_ENGINES,
+        SET_COLOR_THEME,
+        ABOUT,
+    }
 
     /** Initialize the drawer part of the user interface. */
     private void initDrawers() {
@@ -1466,14 +1469,15 @@ public class DroidFish extends Activity
         rightDrawer = findViewById(R.id.right_drawer);
 
         final DrawerItem[] leftItems = new DrawerItem[] {
-            new DrawerItem(ITEM_NEW_GAME, R.string.option_new_game),
-            new DrawerItem(ITEM_EDIT_BOARD, R.string.option_edit_board),
-            new DrawerItem(ITEM_FILE_MENU, R.string.option_file),
-            new DrawerItem(ITEM_SELECT_BOOK, R.string.option_select_book),
-            new DrawerItem(ITEM_MANAGE_ENGINES, R.string.option_manage_engines),
-            new DrawerItem(ITEM_SET_COLOR_THEME, R.string.option_color_theme),
-            new DrawerItem(ITEM_SETTINGS, R.string.option_settings),
-            new DrawerItem(ITEM_ABOUT, R.string.option_about)
+            new DrawerItem(DrawerItemId.NEW_GAME, R.string.option_new_game),
+            new DrawerItem(DrawerItemId.SET_STRENGTH, R.string.set_engine_strength),
+            new DrawerItem(DrawerItemId.EDIT_BOARD, R.string.option_edit_board),
+            new DrawerItem(DrawerItemId.FILE_MENU, R.string.option_file),
+            new DrawerItem(DrawerItemId.SELECT_BOOK, R.string.option_select_book),
+            new DrawerItem(DrawerItemId.MANAGE_ENGINES, R.string.option_manage_engines),
+            new DrawerItem(DrawerItemId.SET_COLOR_THEME, R.string.option_color_theme),
+            new DrawerItem(DrawerItemId.SETTINGS, R.string.option_settings),
+            new DrawerItem(DrawerItemId.ABOUT, R.string.option_about),
         };
         leftDrawer.setAdapter(new ArrayAdapter<>(this,
                                                  R.layout.drawer_list_item,
@@ -1484,9 +1488,9 @@ public class DroidFish extends Activity
         });
 
         final DrawerItem[] rightItems = new DrawerItem[] {
-            new DrawerItem(ITEM_RESIGN, R.string.option_resign_game),
-            new DrawerItem(ITEM_FORCE_MOVE, R.string.option_force_computer_move),
-            new DrawerItem(ITEM_DRAW, R.string.option_draw)
+            new DrawerItem(DrawerItemId.RESIGN, R.string.option_resign_game),
+            new DrawerItem(DrawerItemId.FORCE_MOVE, R.string.option_force_computer_move),
+            new DrawerItem(DrawerItemId.DRAW, R.string.option_draw),
         };
         rightDrawer.setAdapter(new ArrayAdapter<>(this,
                                                   R.layout.drawer_list_item,
@@ -1504,7 +1508,7 @@ public class DroidFish extends Activity
     }
 
     /** React to a selection in the left/right drawers. */
-    private void handleDrawerSelection(int itemId) {
+    private void handleDrawerSelection(DrawerItemId id) {
         drawerLayout.closeDrawer(Gravity.LEFT);
         drawerLayout.closeDrawer(Gravity.RIGHT);
         leftDrawer.clearChoices();
@@ -1512,30 +1516,33 @@ public class DroidFish extends Activity
 
         setAutoMode(AutoMode.OFF);
 
-        switch (itemId) {
-        case ITEM_NEW_GAME:
+        switch (id) {
+        case NEW_GAME:
             showDialog(NEW_GAME_DIALOG);
             break;
-        case ITEM_EDIT_BOARD:
+        case SET_STRENGTH:
+            reShowDialog(SET_STRENGTH_DIALOG);
+            break;
+        case EDIT_BOARD:
             startEditBoard(ctrl.getFEN());
             break;
-        case ITEM_SETTINGS: {
+        case SETTINGS: {
             Intent i = new Intent(DroidFish.this, Preferences.class);
             startActivityForResult(i, RESULT_SETTINGS);
             break;
         }
-        case ITEM_FILE_MENU:
+        case FILE_MENU:
             if (storageAvailable())
                 reShowDialog(FILE_MENU_DIALOG);
             break;
-        case ITEM_RESIGN:
+        case RESIGN:
             if (ctrl.humansTurn())
                 ctrl.resignGame();
             break;
-        case ITEM_FORCE_MOVE:
+        case FORCE_MOVE:
             ctrl.stopSearch();
             break;
-        case ITEM_DRAW:
+        case DRAW:
             if (ctrl.humansTurn()) {
                 if (ctrl.claimDrawIfPossible())
                     ctrl.stopPonder();
@@ -1543,20 +1550,20 @@ public class DroidFish extends Activity
                     DroidFishApp.toast(R.string.offer_draw, Toast.LENGTH_SHORT);
             }
             break;
-        case ITEM_SELECT_BOOK:
+        case SELECT_BOOK:
             if (storageAvailable())
                 reShowDialog(SELECT_BOOK_DIALOG);
             break;
-        case ITEM_MANAGE_ENGINES:
+        case MANAGE_ENGINES:
             if (storageAvailable())
                 reShowDialog(MANAGE_ENGINES_DIALOG);
             else
                 reShowDialog(SELECT_ENGINE_DIALOG_NOMANAGE);
             break;
-        case ITEM_SET_COLOR_THEME:
+        case SET_COLOR_THEME:
             showDialog(SET_COLOR_THEME_DIALOG);
             break;
-        case ITEM_ABOUT:
+        case ABOUT:
             showDialog(ABOUT_DIALOG);
             break;
         }
@@ -2025,6 +2032,7 @@ public class DroidFish extends Activity
     static private final int DELETE_NETWORK_ENGINE_DIALOG = 25;
     static private final int CLIPBOARD_DIALOG = 26;
     static private final int SELECT_FEN_FILE_DIALOG = 27;
+    static private final int SET_STRENGTH_DIALOG = 28;
 
     /** Remove and show a dialog. */
     void reShowDialog(int id) {
@@ -2036,6 +2044,7 @@ public class DroidFish extends Activity
     protected Dialog onCreateDialog(int id) {
         switch (id) {
         case NEW_GAME_DIALOG:                return newGameDialog();
+        case SET_STRENGTH_DIALOG:            return setStrengthDialog();
         case PROMOTE_DIALOG:                 return promoteDialog();
         case BOARD_MENU_DIALOG:              return boardMenuDialog();
         case FILE_MENU_DIALOG:               return fileMenuDialog();
@@ -2076,6 +2085,106 @@ public class DroidFish extends Activity
         return builder.create();
     }
 
+    private Dialog setStrengthDialog() {
+        EloStrengthSetter m = new EloStrengthSetter();
+        return m.getDialog();
+    }
+
+    /** Handle user interface to set engine strength. */
+    private class EloStrengthSetter {
+        private final EloData eloData = ctrl.eloData();
+
+        private CheckBox checkBox;
+        private TextView eloLabel;
+        private EditText editTxt;
+        private SeekBar seekBar;
+
+        private int progressToElo(int p) {
+            return eloData.minElo + p;
+        }
+
+        private int eloToProgress(int elo) {
+            return elo - eloData.minElo;
+        }
+
+        private void updateText(int elo) {
+            String txt = Integer.valueOf(elo).toString();
+            if (!txt.equals(editTxt.getText().toString())) {
+                editTxt.setText(txt);
+                editTxt.setSelection(txt.length());
+            }
+        }
+
+        private void updateEnabledState(boolean enabled) {
+            eloLabel.setEnabled(enabled);
+            editTxt.setEnabled(enabled);
+            seekBar.setEnabled(enabled);
+        }
+
+        public Dialog getDialog() {
+            if (!eloData.canChangeStrength()) {
+                DroidFishApp.toast(R.string.engine_cannot_reduce_strength, Toast.LENGTH_LONG);
+                return null;
+            }
+            AlertDialog.Builder builder = new AlertDialog.Builder(DroidFish.this);
+            builder.setTitle(R.string.set_engine_strength);
+            View content = View.inflate(DroidFish.this, R.layout.set_strength, null);
+            builder.setView(content);
+
+            checkBox = content.findViewById(R.id.strength_checkbox);
+            eloLabel = content.findViewById(R.id.strength_elolabel);
+            editTxt = content.findViewById(R.id.strength_edittext);
+            seekBar = content.findViewById(R.id.strength_seekbar);
+
+            checkBox.setChecked(eloData.limitStrength);
+            seekBar.setMax(eloToProgress(eloData.maxElo));
+            seekBar.setProgress(eloToProgress(eloData.elo));
+            updateText(eloData.elo);
+            updateEnabledState(eloData.limitStrength);
+
+            checkBox.setOnCheckedChangeListener((button, isChecked) -> {
+                updateEnabledState(isChecked);
+            });
+            seekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
+                @Override
+                public void onStopTrackingTouch(SeekBar seekBar) { }
+                @Override
+                public void onStartTrackingTouch(SeekBar seekBar) { }
+                @Override
+                public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
+                    updateText(progressToElo(progress));
+                }
+            });
+            editTxt.addTextChangedListener(new TextWatcher() {
+                @Override
+                public void onTextChanged(CharSequence s, int start, int before, int count) {
+                    String txt = editTxt.getText().toString();
+                    try {
+                        int elo = Integer.parseInt(txt);
+                        int p = eloToProgress(elo);
+                        if (p != seekBar.getProgress())
+                            seekBar.setProgress(p);
+                        updateText(progressToElo(p));
+                    } catch (NumberFormatException ignore) {
+                    }
+                }
+                @Override
+                public void beforeTextChanged(CharSequence s, int start, int count, int after) { }
+                @Override
+                public void afterTextChanged(Editable s) { }
+            });
+
+            builder.setNegativeButton(R.string.cancel, null);
+            builder.setPositiveButton(android.R.string.ok, (dialog, which) -> {
+                boolean limitStrength = checkBox.isChecked();
+                int elo = progressToElo(seekBar.getProgress());
+                ctrl.setStrength(limitStrength, elo);
+            });
+
+            return builder.create();
+        }
+    }
+
     private void startNewGame(int type) {
         if (type != 2) {
             int gameModeType = (type == 0) ? GameMode.PLAYER_WHITE : GameMode.PLAYER_BLACK;
@@ -2091,7 +2200,7 @@ public class DroidFish extends Activity
         ctrl.newGame(gameMode, tcData);
         ctrl.startGame();
         setBoardFlip(true);
-        updateEngineTitle();
+        updateEngineTitle(ctrl.eloData().getEloToUse()); // Game mode affects Elo setting
     }
 
     private Dialog promoteDialog() {
@@ -2502,9 +2611,8 @@ public class DroidFish extends Activity
                     editor.putString("engine", engine);
                     editor.apply();
                     dialog.dismiss();
-                    int strength = settings.getInt("strength", 1000);
                     setEngineOptions(false);
-                    setEngineStrength(engine, strength);
+                    setEngine(engine);
                 });
         builder.setOnCancelListener(dialog -> {
             if (!abortOnCancel)
@@ -2845,8 +2953,7 @@ public class DroidFish extends Activity
         int numPV = this.numPV;
         final int maxPV = ctrl.maxPV();
         if (gameMode.analysisMode()) {
-            numPV = Math.min(numPV, maxPV);
-            numPV = Math.max(numPV, 1);
+            numPV = Math.min(Math.max(numPV, 1), maxPV);
             if (maxPV > 1) {
                 lst.add(getString(R.string.num_variations)); actions.add(MULTIPV_SET);
             }
@@ -2988,11 +3095,9 @@ public class DroidFish extends Activity
 
             seekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
                 @Override
-                public void onStopTrackingTouch(SeekBar seekBar) {
-                }
+                public void onStopTrackingTouch(SeekBar seekBar) { }
                 @Override
-                public void onStartTrackingTouch(SeekBar seekBar) {
-                }
+                public void onStartTrackingTouch(SeekBar seekBar) { }
                 @Override
                 public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                     int nPV = progressToNumPV(progress, maxPV);
@@ -3014,11 +3119,9 @@ public class DroidFish extends Activity
                     }
                 }
                 @Override
-                public void beforeTextChanged(CharSequence s, int start, int count, int after) {
-                }
+                public void beforeTextChanged(CharSequence s, int start, int count, int after) { }
                 @Override
-                public void afterTextChanged(Editable s) {
-                }
+                public void afterTextChanged(Editable s) { }
             });
 
             builder.setNegativeButton(R.string.cancel, null);
@@ -3349,9 +3452,8 @@ public class DroidFish extends Activity
                 editor.putString("engine", engine);
                 editor.apply();
                 dialog.dismiss();
-                int strength = settings.getInt("strength", 1000);
                 setEngineOptions(false);
-                setEngineStrength(engine, strength);
+                setEngine(engine);
             }
             dialog.cancel();
             reShowDialog(NETWORK_ENGINE_DIALOG);
@@ -3553,22 +3655,22 @@ public class DroidFish extends Activity
     @Override
     public void reportInvalidMove(Move m) {
         String msg = String.format(Locale.US, "%s %s-%s",
-                getString(R.string.invalid_move),
-                TextIO.squareToString(m.from), TextIO.squareToString(m.to));
+                                   getString(R.string.invalid_move),
+                                   TextIO.squareToString(m.from), TextIO.squareToString(m.to));
         DroidFishApp.toast(msg, Toast.LENGTH_SHORT);
     }
 
     @Override
     public void reportEngineName(String engine) {
         String msg = String.format(Locale.US, "%s: %s",
-                getString(R.string.engine), engine);
+                                   getString(R.string.engine), engine);
         DroidFishApp.toast(msg, Toast.LENGTH_SHORT);
     }
 
     @Override
     public void reportEngineError(String errMsg) {
         String msg = String.format(Locale.US, "%s: %s",
-                getString(R.string.engine_error), errMsg);
+                                   getString(R.string.engine_error), errMsg);
         DroidFishApp.toast(msg, Toast.LENGTH_LONG);
     }
 
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/GUIInterface.java b/DroidFishApp/src/main/java/org/petero/droidfish/GUIInterface.java
index 4ccb089..5a96bfe 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/GUIInterface.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/GUIInterface.java
@@ -86,7 +86,7 @@ public interface GUIInterface {
     void setRemainingTime(int wTime, int bTime, int nextUpdate);
 
     /** Update engine title text. */
-    void updateEngineTitle();
+    void updateEngineTitle(int elo);
 
     /** Update title with the material difference. */
     void updateMaterialDifferenceTitle(Util.MaterialDiff diff);
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/activities/util/SeekBarPreference.java b/DroidFishApp/src/main/java/org/petero/droidfish/activities/util/SeekBarPreference.java
index b33d64c..2808351 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/activities/util/SeekBarPreference.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/activities/util/SeekBarPreference.java
@@ -91,9 +91,7 @@ public class SeekBarPreference extends Preference implements OnSeekBarChangeList
             builder.setView(selectPercentageBinding.getRoot());
             String title = "";
             String key = getKey();
-            if (key.equals("strength")) {
-                title = getContext().getString(R.string.edit_strength);
-            } else if (key.equals("bookRandom")) {
+            if (key.equals("bookRandom")) {
                 title = getContext().getString(R.string.edit_randomization);
             }
             builder.setTitle(title);
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/DroidComputerPlayer.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/DroidComputerPlayer.java
index f8efffc..08dce30 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/DroidComputerPlayer.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/DroidComputerPlayer.java
@@ -109,7 +109,7 @@ public class DroidComputerPlayer {
         int movesToGo;          // Number of moves to next time control
 
         String engine;          // Engine name (identifier)
-        int strength;           // Engine strength setting (0 - 1000)
+        int elo;                // Engine UCI_Elo setting, or Integer.MAX_VALUE for full strength
         int numPV;              // Number of PV lines to compute
 
         boolean ponderEnabled;  // True if pondering enabled, for engine time management
@@ -145,14 +145,14 @@ public class DroidComputerPlayer {
          * @param ponderEnabled True if pondering is enabled in the GUI. Can affect time management.
          * @param ponderMove Move to ponder, or null for non-ponder search.
          * @param engine Chess engine to use for searching.
-         * @param strength Engine strength setting.
+         * @param elo Engine Elo strength setting.
          */
         public static SearchRequest searchRequest(int id, long now,
                                                   Position prevPos, ArrayList<Move> mList,
                                                   Position currPos, boolean drawOffer,
                                                   int wTime, int bTime, int wInc, int bInc, int movesToGo,
                                                   boolean ponderEnabled, Move ponderMove,
-                                                  String engine, int strength) {
+                                                  String engine, int elo) {
             SearchRequest sr = new SearchRequest();
             sr.searchId = id;
             sr.startTime = now;
@@ -168,7 +168,7 @@ public class DroidComputerPlayer {
             sr.bInc = bInc;
             sr.movesToGo = movesToGo;
             sr.engine = engine;
-            sr.strength = strength;
+            sr.elo = elo;
             sr.numPV = 1;
             sr.ponderEnabled = ponderEnabled;
             sr.ponderMove = ponderMove;
@@ -204,7 +204,7 @@ public class DroidComputerPlayer {
             sr.isAnalyze = true;
             sr.wTime = sr.bTime = sr.wInc = sr.bInc = sr.movesToGo = 0;
             sr.engine = engine;
-            sr.strength = 1000;
+            sr.elo = Integer.MAX_VALUE;
             sr.numPV = numPV;
             sr.ponderEnabled = false;
             sr.ponderMove = null;
@@ -310,6 +310,56 @@ public class DroidComputerPlayer {
         }
     }
 
+    public static class EloData {
+        public boolean limitStrength = false; // True if engine strength reduction is enabled
+        public int elo = 0;                   // Current strength setting
+        public int minElo = 0;                // Smallest possible Elo value
+        public int maxElo = 0;                // Largest possible Elo value
+
+        /** Return true if engine is able to change the playing strength. */
+        public boolean canChangeStrength() {
+            return minElo < maxElo;
+        }
+
+        /** Get current Elo setting.
+         *  Return MAX_VALUE if reduced strength not enabled or not supported. */
+        public int getEloToUse() {
+            if (canChangeStrength() && limitStrength)
+                return elo;
+            return Integer.MAX_VALUE;
+        }
+    }
+
+    /** Return engine Elo strength data. */
+    public synchronized EloData getEloData() {
+        EloData ret = new EloData();
+        UCIEngine uci = uciEngine;
+        if (uci != null) {
+            UCIOptions opts = uci.getUCIOptions();
+            UCIOptions.OptionBase lsOpt = opts.getOption("UCI_LimitStrength");
+            UCIOptions.OptionBase eloOpt = opts.getOption("UCI_Elo");
+            if (lsOpt instanceof UCIOptions.CheckOption &&
+                eloOpt instanceof UCIOptions.SpinOption) {
+                ret.limitStrength = ((UCIOptions.CheckOption)lsOpt).value;
+                UCIOptions.SpinOption eloSpin = (UCIOptions.SpinOption)eloOpt;
+                ret.elo = eloSpin.value;
+                ret.minElo = eloSpin.minValue;
+                ret.maxElo = eloSpin.maxValue;
+            }
+        }
+        return ret;
+    }
+
+    /** Set engine UCI strength parameters. */
+    public void setStrength(int elo) {
+        Map<String,String> opts = new TreeMap<>();
+        boolean limitStrength = elo != Integer.MAX_VALUE;
+        opts.put("UCI_LimitStrength", limitStrength ? "true" : "false");
+        if (limitStrength)
+            opts.put("UCI_Elo", String.valueOf(elo));
+        setEngineUCIOptions(opts);
+    }
+
     /** Return all book moves, both as a formatted string and as a list of moves. */
     public final Pair<String, ArrayList<Move>> getBookHints(Position pos, boolean localized) {
         return book.getAllBookMoves(pos, localized);
@@ -571,7 +621,7 @@ public class DroidComputerPlayer {
 
         // Set strength and MultiPV parameters
         clearInfo();
-        uciEngine.setStrength(searchRequest.strength);
+        uciEngine.setEloStrength(searchRequest.elo);
         if (maxPV > 1) {
             int num = Math.min(maxPV, searchRequest.numPV);
             uciEngine.setOption("MultiPV", num);
@@ -721,6 +771,7 @@ public class DroidComputerPlayer {
                 uci.writeLineToEngine("ucinewgame");
                 uci.writeLineToEngine("isready");
                 engineState.setState(MainState.WAIT_READY);
+                listener.notifyEngineInitialized();
             }
             break;
         }
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/ExternalEngine.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/ExternalEngine.java
index d3b97ad..f58013f 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/ExternalEngine.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/ExternalEngine.java
@@ -236,10 +236,6 @@ public class ExternalEngine extends UCIEngineBase {
         return true;
     }
 
-    @Override
-    public void setStrength(int strength) {
-    }
-
     @Override
     public String readLineFromEngine(int timeoutMillis) {
         String ret = inLines.readLine(timeoutMillis);
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/InternalStockFish.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/InternalStockFish.java
index ce1c290..3ddf57c 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/InternalStockFish.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/InternalStockFish.java
@@ -46,9 +46,9 @@ public class InternalStockFish extends ExternalEngine {
     }
 
     @Override
-    protected boolean configurableOption(String name) {
+    protected boolean editableOption(String name) {
         name = name.toLowerCase(Locale.US);
-        if (!super.configurableOption(name))
+        if (!super.editableOption(name))
             return false;
         if (name.equals("skill level") || name.equals("write debug log") ||
             name.equals("write search log"))
@@ -56,11 +56,6 @@ public class InternalStockFish extends ExternalEngine {
         return true;
     }
 
-    @Override
-    public final void setStrength(int strength) {
-        setOption("Skill Level", strength/50);
-    }
-
     private long readCheckSum(File f) {
         try (InputStream is = new FileInputStream(f);
              DataInputStream dis = new DataInputStream(is)) {
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/NetworkEngine.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/NetworkEngine.java
index fc12b15..cc6c3ae 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/NetworkEngine.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/NetworkEngine.java
@@ -228,10 +228,6 @@ public class NetworkEngine extends UCIEngineBase {
         return true;
     }
 
-    @Override
-    public void setStrength(int strength) {
-    }
-
     @Override
     public String readLineFromEngine(int timeoutMillis) {
         String ret = engineToGui.readLine(timeoutMillis);
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngine.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngine.java
index 852e728..ecd3caa 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngine.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngine.java
@@ -67,8 +67,9 @@ public interface UCIEngine {
     /** Write a line to the engine. \n will be added automatically. */
     void writeLineToEngine(String data);
 
-    /** Set the engine strength, allowed values 0 - 1000. */
-    void setStrength(int strength);
+    /** Temporarily set the engine Elo strength to use for the next search.
+     *  Integer.MAX_VALUE means full strength. */
+    void setEloStrength(int elo);
 
     /** Set an engine integer option. */
     void setOption(String name, int value);
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngineBase.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngineBase.java
index b540e45..4350720 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngineBase.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIEngineBase.java
@@ -27,6 +27,7 @@ import java.util.Arrays;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Properties;
+import java.util.TreeMap;
 
 import org.petero.droidfish.EngineOptions;
 import org.petero.droidfish.engine.cuckoochess.CuckooChessEngine;
@@ -80,14 +81,15 @@ public abstract class UCIEngineBase implements UCIEngine {
             iniOptions.load(is);
         } catch (IOException ignore) {
         }
+        Map<String,String> opts = new TreeMap<>();
         for (Map.Entry<Object,Object> ent : iniOptions.entrySet()) {
             if (ent.getKey() instanceof String && ent.getValue() instanceof String) {
                 String key = ((String)ent.getKey()).toLowerCase(Locale.US);
                 String value = (String)ent.getValue();
-                if (configurableOption(key))
-                    setOption(key, value);
+                opts.put(key, value);
             }
         }
+        setUCIOptions(opts);
     }
 
     @Override
@@ -125,12 +127,11 @@ public abstract class UCIEngineBase implements UCIEngine {
     /** Get engine UCI options file. */
     protected abstract File getOptionsFile();
 
-    /** Return true if the UCI option can be changed by the user. */
-    protected boolean configurableOption(String name) {
+    /** Return true if the UCI option can be edited in the "Engine Options" dialog. */
+    protected boolean editableOption(String name) {
         name = name.toLowerCase(Locale.US);
         if (name.startsWith("uci_")) {
-            String[] allowed = { "uci_limitstrength", "uci_elo" };
-            return Arrays.asList(allowed).contains(name);
+            return false;
         } else {
             String[] ignored = { "hash", "ponder", "multipv",
                                  "gaviotatbpath", "syzygypath" };
@@ -138,6 +139,17 @@ public abstract class UCIEngineBase implements UCIEngine {
         }
     }
 
+    /** Return true if the UCI option can be modified by the user, either directly
+     *  from the "Engine Options" dialog or indirectly, for example from the
+     *  "Set Engine Strength" dialog. */
+    private boolean configurableOption(String name) {
+        if (editableOption(name))
+            return true;
+        name = name.toLowerCase(Locale.US);
+        String[] configurable = { "uci_limitstrength", "uci_elo" };
+        return Arrays.asList(configurable).contains(name);
+    }
+
     @Override
     public void shutDown() {
         if (processAlive) {
@@ -221,7 +233,7 @@ public abstract class UCIEngineBase implements UCIEngine {
                     int maxV = Integer.parseInt(maxVal);
                     if (minV <= defV && defV <= maxV)
                         option = new UCIOptions.SpinOption(name, minV, maxV, defV);
-                } catch (NumberFormatException ex) {
+                } catch (NumberFormatException ignore) {
                 }
             }
         } else if (type.equals("combo")) {
@@ -241,8 +253,7 @@ public abstract class UCIEngineBase implements UCIEngine {
         }
 
         if (option != null) {
-            if (!configurableOption(name))
-                option.visible = false;
+            option.visible = editableOption(name);
             options.addOption(option);
         }
         return option;
@@ -253,6 +264,21 @@ public abstract class UCIEngineBase implements UCIEngine {
         return options.contains(optName);
     }
 
+    @Override
+    public final void setEloStrength(int elo) {
+        String lsName = "UCI_LimitStrength";
+        boolean limit = elo != Integer.MAX_VALUE;
+        UCIOptions.OptionBase o = options.getOption(lsName);
+        if (o instanceof UCIOptions.CheckOption) {
+            // Don't use setOption() since this value reflects current search parameters,
+            // not user specified strength settings, so should not be saved in .ini file.
+            writeLineToEngine(String.format(Locale.US, "setoption name %s value %s",
+                                            lsName, limit ? "true" : "false"));
+        }
+        if (limit)
+            setOption("UCI_Elo", elo);
+    }
+
     @Override
     public final void setOption(String name, int value) {
         setOption(name, String.format(Locale.US, "%d", value));
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIOptions.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIOptions.java
index f382823..697616f 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIOptions.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/UCIOptions.java
@@ -41,7 +41,7 @@ public class UCIOptions implements Serializable, Cloneable {
         private static final long serialVersionUID = 1L;
         public String name;
         public Type type;
-        public boolean visible = true;
+        public boolean visible = true; // True if visible in "Engine Options" dialog
 
         @Override
         public OptionBase clone() throws CloneNotSupportedException {
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/engine/cuckoochess/CuckooChessEngine.java b/DroidFishApp/src/main/java/org/petero/droidfish/engine/cuckoochess/CuckooChessEngine.java
index 330d6a2..d6a485e 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/engine/cuckoochess/CuckooChessEngine.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/engine/cuckoochess/CuckooChessEngine.java
@@ -74,9 +74,9 @@ public class CuckooChessEngine extends UCIEngineBase {
     }
 
     @Override
-    protected boolean configurableOption(String name) {
+    protected boolean editableOption(String name) {
         name = name.toLowerCase(Locale.US);
-        if (!super.configurableOption(name))
+        if (!super.editableOption(name))
             return false;
         if (name.equals("strength"))
             return false;
@@ -88,11 +88,6 @@ public class CuckooChessEngine extends UCIEngineBase {
         return true;
     }
 
-    @Override
-    public final void setStrength(int strength) {
-        setOption("strength", strength);
-    }
-
     private void mainLoop(LocalPipe is, LocalPipe os) {
         String line;
         while ((line = is.readLine()) != null) {
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/DroidChessController.java b/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/DroidChessController.java
index ca9eb54..4824a46 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/DroidChessController.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/DroidChessController.java
@@ -41,6 +41,7 @@ import org.petero.droidfish.book.BookOptions;
 import org.petero.droidfish.book.EcoDb;
 import org.petero.droidfish.engine.DroidComputerPlayer;
 import org.petero.droidfish.engine.UCIOptions;
+import org.petero.droidfish.engine.DroidComputerPlayer.EloData;
 import org.petero.droidfish.engine.DroidComputerPlayer.SearchRequest;
 import org.petero.droidfish.engine.DroidComputerPlayer.SearchType;
 import org.petero.droidfish.gamelogic.Game.CommentInfo;
@@ -60,7 +61,6 @@ public class DroidChessController {
     private PGNOptions pgnOptions;
 
     private String engine = "";
-    private int strength = 1000;
     private int numPV = 1;
 
     private SearchListener listener;
@@ -146,13 +146,15 @@ public class DroidChessController {
             if (!gameMode.playerWhite() || !gameMode.playerBlack())
                 setPlayerNames(game); // If computer player involved, set player names
             updateGameMode();
-            abortSearch();
-            updateComputeThreads();
-            gui.updateEngineTitle();
-            updateGUI();
+            gui.updateEngineTitle(getEloToUse()); // Game mode affects Elo setting
+            restartSearch();
         }
     }
 
+    private int getEloToUse() {
+        return eloData().getEloToUse();
+    }
+
     public final GameMode getGameMode() {
         return gameMode;
     }
@@ -179,30 +181,49 @@ public class DroidChessController {
             engineOptions = options;
             if (computerPlayer != null)
                 computerPlayer.setEngineOptions(engineOptions);
-            if (restart && (game != null)) {
-                abortSearch();
-                updateComputeThreads();
-                updateGUI();
-            }
+            if (restart)
+                restartSearch();
         }
     }
 
-    /** Set engine and engine strength. Restart computer thinking if appropriate.
-     * @param engine Name of engine.
-     * @param strength Engine strength, 0 - 1000. */
-    public final synchronized void setEngineStrength(String engine, int strength) {
-        boolean newEngine = !engine.equals(this.engine);
-        if (newEngine || (strength != this.strength)) {
-            this.engine = engine;
-            this.strength = strength;
-            if (game != null) {
-                abortSearch();
-                updateComputeThreads();
-                updateGUI();
-            }
+    private void restartSearch() {
+        if (game != null) {
+            abortSearch();
+            updateComputeThreads();
+            updateGUI();
         }
     }
 
+    /** Set engine. Restart computer thinking if appropriate. */
+    public final synchronized void setEngine(String engine) {
+        if (!engine.equals(this.engine)) {
+            this.engine = engine;
+            restartSearch();
+        }
+    }
+
+    /** Set engine strength. Restart computer thinking if appropriate. */
+    public final synchronized void setStrength(boolean limitStrength, int elo) {
+        EloData d = eloData();
+        int oldElo = d.getEloToUse();
+        d.limitStrength = limitStrength;
+        d.elo = elo;
+        int newElo = d.getEloToUse();
+        if (oldElo != newElo) {
+            if (computerPlayer != null)
+                computerPlayer.setStrength(newElo);
+            restartSearch();
+            gui.updateEngineTitle(newElo);
+        }
+    }
+
+    /** Return engine Elo strength data. */
+    public final synchronized EloData eloData() {
+        if (computerPlayer == null)
+            return new EloData();
+        return computerPlayer.getEloData();
+    }
+
     /** Set engine UCI options. */
     public final synchronized void setEngineUCIOptions(Map<String,String> uciOptions) {
         if (computerPlayer != null)
@@ -233,8 +254,7 @@ public class DroidChessController {
              DataInputStream dis = new DataInputStream(bais)) {
             game.readFromStream(dis, version);
             game.tree.translateMoves();
-        } catch (IOException ignore) {
-        } catch (ChessParseError ignore) {
+        } catch (IOException|ChessParseError ignore) {
         }
     }
 
@@ -383,9 +403,7 @@ public class DroidChessController {
         if (humansTurn()) {
             int varNo = game.tree.addMove("--", "", 0, "", "");
             game.tree.goForward(varNo);
-            abortSearch();
-            updateComputeThreads();
-            updateGUI();
+            restartSearch();
             gui.setSelection(-1);
         }
     }
@@ -596,11 +614,8 @@ public class DroidChessController {
         clampedNumPV = Math.max(clampedNumPV, 1);
         boolean modified = clampedNumPV != this.numPV;
         this.numPV = numPV;
-        if (modified) {
-            abortSearch();
-            updateComputeThreads();
-            updateGUI();
-        }
+        if (modified)
+            restartSearch();
     }
 
     /** Request computer player to make a move immediately. */
@@ -757,7 +772,7 @@ public class DroidChessController {
                 } else if (currTime < 999950) {
                     statStrTmp.append(String.format(Locale.US, " t:%.1f", currTime / 1000.0));
                 } else {
-                    statStrTmp.append(String.format(Locale.US, " t:%d", (int)((currTime + 500) / 1000)));
+                    statStrTmp.append(String.format(Locale.US, " t:%d", (currTime + 500) / 1000));
                 }
                 statStrTmp.append(" n:");
                 appendWithPrefix(statStrTmp, currNodes);
@@ -900,18 +915,25 @@ public class DroidChessController {
         }
 
         @Override
-        public void notifySearchResult(final int id, final String cmd, final Move ponder) {
+        public void notifySearchResult(int id, String cmd, Move ponder) {
             new Thread(() -> gui.runOnUIThread(() -> makeComputerMove(id, cmd, ponder))).start();
         }
 
         @Override
-        public void notifyEngineName(final String engineName) {
+        public void notifyEngineName(String engineName) {
             gui.runOnUIThread(() -> {
                 updatePlayerNames(engineName);
                 gui.reportEngineName(engineName);
             });
         }
 
+        @Override
+        public void notifyEngineInitialized() {
+            gui.runOnUIThread(() -> {
+                gui.updateEngineTitle(eloData().getEloToUse());
+            });
+        }
+
         @Override
         public void reportEngineError(final String errMsg) {
             gui.runOnUIThread(() -> gui.reportEngineError(errMsg));
@@ -998,7 +1020,7 @@ public class DroidChessController {
                         game.haveDrawOffer(),
                         wTime, bTime, wInc, bInc, movesToGo,
                         gui.ponderMode(), fPonderMove,
-                        engine, strength);
+                        engine, getEloToUse());
                 computerPlayer.queueSearchRequest(sr);
             } else {
                 computerPlayer.queueStartEngine(searchId, engine);
@@ -1033,8 +1055,9 @@ public class DroidChessController {
             String engine = "Computer";
             if (computerPlayer != null) {
                 engine = computerPlayer.getEngineName();
-                if (strength < 1000)
-                    engine += String.format(Locale.US, " (%.1f%%)", strength * 0.1);
+                int elo = getEloToUse();
+                if (elo != Integer.MAX_VALUE)
+                    engine += String.format(Locale.US, " (%d)", elo);
             }
             String player = gui.playerName();
             String white = gameMode.playerWhite() ? player : engine;
@@ -1045,8 +1068,9 @@ public class DroidChessController {
 
     private synchronized void updatePlayerNames(String engineName) {
         if (game != null) {
-            if (strength < 1000)
-                engineName += String.format(Locale.US, " (%.1f%%)", strength * 0.1);
+            int elo = getEloToUse();
+            if (elo != Integer.MAX_VALUE)
+                engineName += String.format(Locale.US, " (%d)", elo);
             String white = gameMode.playerWhite() ? game.tree.white : engineName;
             String black = gameMode.playerBlack() ? game.tree.black : engineName;
             game.tree.setPlayerNames(white, black);
diff --git a/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/SearchListener.java b/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/SearchListener.java
index 8949e7e..951e998 100644
--- a/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/SearchListener.java
+++ b/DroidFishApp/src/main/java/org/petero/droidfish/gamelogic/SearchListener.java
@@ -84,4 +84,7 @@ public interface SearchListener {
 
     /** Report engine error. */
     void reportEngineError(String errMsg);
+
+    /** Report that engine has been initialized. */
+    void notifyEngineInitialized();
 }
diff --git a/DroidFishApp/src/main/res/layout/set_strength.xml b/DroidFishApp/src/main/res/layout/set_strength.xml
new file mode 100644
index 0000000..2d9f0e5
--- /dev/null
+++ b/DroidFishApp/src/main/res/layout/set_strength.xml
@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical">
+
+    <CheckBox
+        android:id="@+id/strength_checkbox"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:layout_marginTop="10dp"
+        android:text="@string/limit_strength"/>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="horizontal">
+
+        <TextView
+            android:id="@+id/strength_elolabel"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginLeft="5dp"
+            android:text="Elo:" />
+
+        <EditText
+            android:id="@+id/strength_edittext"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1.0"
+            android:inputType="number" />
+    </LinearLayout>
+
+    <SeekBar
+        android:id="@+id/strength_seekbar"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="10dp" />
+</LinearLayout>
diff --git a/DroidFishApp/src/main/res/layout/title.xml b/DroidFishApp/src/main/res/layout/title.xml
index 6a964c5..350f193 100644
--- a/DroidFishApp/src/main/res/layout/title.xml
+++ b/DroidFishApp/src/main/res/layout/title.xml
@@ -44,6 +44,7 @@
             android:gravity="center"
             android:textSize="14sp"
             android:tag="title"
+            android:ellipsize="middle"
             android:text="@string/app_name" />
 
         <TextView
diff --git a/DroidFishApp/src/main/res/values-be/strings.xml b/DroidFishApp/src/main/res/values-be/strings.xml
index 569ad80..bc289b6 100644
--- a/DroidFishApp/src/main/res/values-be/strings.xml
+++ b/DroidFishApp/src/main/res/values-be/strings.xml
@@ -50,7 +50,6 @@
     <string name="tools_menu">Прылады</string>
     <string name="load_save_menu">Загрузіць/Захаваць партыю</string>
     <string name="goto_move">Зрабіць ход</string>
-    <string name="edit_strength">Змяніць ровень складанасці</string>
     <string name="edit_randomization">Змяніць рандамізацыю (выпадковасць)</string>
     <string name="invalid_number_format">Няправільны фармат ліку</string>
     <string name="side_to_move">Задаць кірунак ходу</string>
@@ -273,8 +272,6 @@
     <string name="prefs_playerNameFlip_title">Паварочваць дошку: гулец</string>
     <string name="prefs_playerNameFlip_summary">Скарыстаць імя гульца для аўтаматычнага павароту дошкі</string>
     <string name="prefs_engine_settings">Налады рухавічка</string>
-    <string name="prefs_strength_title">Сіла гульні</string>
-    <string name="prefs_strength_summary">Падтрымваецца толькі ўнутранымі рухавічкамі. Рэжым аналізу заўсёды скарыстае поўную сілу.</string>
     <string name="prefs_ponderMode_title">Разважанне</string>
     <string name="prefs_ponderMode_summary">Дазволіць рухавічку абдумванне падчас чакання ходу апанента. Падтрымваецца большасцю рухавічкоў.</string>
     <string name="prefs_hash_title">Хэш-табліца</string>
diff --git a/DroidFishApp/src/main/res/values-de/strings.xml b/DroidFishApp/src/main/res/values-de/strings.xml
index b0f8abc..6e313ec 100644
--- a/DroidFishApp/src/main/res/values-de/strings.xml
+++ b/DroidFishApp/src/main/res/values-de/strings.xml
@@ -50,7 +50,6 @@ Um gegebenenfalls Strom zu sparen, ist es empfehlenswert, dass Sie diese Paramet
     <string name="tools_menu">Hilfsmittel</string>
     <string name="load_save_menu">Partie laden/speichern</string>
     <string name="goto_move">Gehe zu Zug</string>
-    <string name="edit_strength">Spielstärke ändern</string>
     <string name="edit_randomization">Randomisierung ändern</string>
     <string name="invalid_number_format">Ungültiges Zahlenformat</string>
     <string name="side_to_move">Seite am Zug</string>
@@ -273,8 +272,6 @@ Um gegebenenfalls Strom zu sparen, ist es empfehlenswert, dass Sie diese Paramet
     <string name="prefs_playerNameFlip_title">Spielfeld nach Namen drehen</string>
     <string name="prefs_playerNameFlip_summary">Spielfeld in Abhängigkeit vom Spielernamen drehen</string>
     <string name="prefs_engine_settings">Engine-Einstellungen</string>
-    <string name="prefs_strength_title">Spielstärke</string>
-    <string name="prefs_strength_summary">Wird nur von internen Engines unterstützt. Im Analyse-Modus wird stets die volle Stärke verwendet.</string>
     <string name="prefs_ponderMode_title">Vorausberechnung</string>
     <string name="prefs_ponderMode_summary">Vorausberechnung von Zügen durch die Engine, wenn der Spieler am Zug ist (von den meisten Engines unterstützt)</string>
     <string name="prefs_hash_title">Hash-Tabelle</string>
diff --git a/DroidFishApp/src/main/res/values-es/strings.xml b/DroidFishApp/src/main/res/values-es/strings.xml
index 8f5d069..ca437a5 100644
--- a/DroidFishApp/src/main/res/values-es/strings.xml
+++ b/DroidFishApp/src/main/res/values-es/strings.xml
@@ -50,7 +50,6 @@ Si está usted utilizando la batería, se recomienda que cambie los ajustes para
     <string name="tools_menu">Herramientas</string>
     <string name="load_save_menu">Cargar/Guardar Partida</string>
     <string name="goto_move">Ir a la jugada</string>
-    <string name="edit_strength">Editar Fuerza de juego</string>
     <string name="edit_randomization">Editar Aleatoriedad</string>
     <string name="invalid_number_format"> Formato de número no válido</string>
     <string name="side_to_move">Turno de juego</string>
@@ -273,8 +272,6 @@ Si está usted utilizando la batería, se recomienda que cambie los ajustes para
     <string name="prefs_playerNameFlip_title">Invertir tablero : Jugador</string>
     <string name="prefs_playerNameFlip_summary">Utilizar el nombre del jugador para invertir el tablero automáticamente</string>
     <string name="prefs_engine_settings">Ajustes del Motor/Programa</string>
-    <string name="prefs_strength_title">Fuerza/Nivel de Juego</string>
-    <string name="prefs_strength_summary">Soportado únicamente por los motores internos. El modo análisis siempre utiliza fuerza máxima.</string>
     <string name="prefs_ponderMode_title">Pensar siempre</string>
     <string name="prefs_ponderMode_summary">Dejar calcular al motor mientras espera la jugada del oponente. Lo incorporan la mayoría de los motores.</string>
     <string name="prefs_hash_title">Tablas Hash</string>
diff --git a/DroidFishApp/src/main/res/values-fr/strings.xml b/DroidFishApp/src/main/res/values-fr/strings.xml
index 799ba2c..e1e3ff4 100644
--- a/DroidFishApp/src/main/res/values-fr/strings.xml
+++ b/DroidFishApp/src/main/res/values-fr/strings.xml
@@ -50,7 +50,6 @@ Lorsque que vous êtes sur batterie, il est recommandé de changer les paramètr
     <string name="tools_menu">Outils</string>
     <string name="load_save_menu">Charger/Sauvegarder une partie</string>
     <string name="goto_move">Aller au coup</string>
-    <string name="edit_strength">Modifier le niveau</string>
     <string name="edit_randomization">Modifier la randomisation</string>
     <string name="invalid_number_format">Format du nombre non valide</string>
     <string name="side_to_move">Camp au trait</string>
@@ -273,8 +272,6 @@ Lorsque que vous êtes sur batterie, il est recommandé de changer les paramètr
     <string name="prefs_playerNameFlip_title">Disposition de l\'échiquier: Joueur</string>
     <string name="prefs_playerNameFlip_summary">Utiliser le nom du joueur pour disposer automatiquement l\'échiquier</string>
     <string name="prefs_engine_settings">Paramètres du module</string>
-    <string name="prefs_strength_title">Niveau de jeu</string>
-    <string name="prefs_strength_summary">Supporté uniquement par les modules internes. Le mode Analyse utilisera toujours le niveau maximal.</string>
     <string name="prefs_ponderMode_title">Réflexion permanente</string>
     <string name="prefs_ponderMode_summary">Laisser le module actif lors du coup de l\'opposant. Supporté par la plupart des modules.</string>
     <string name="prefs_hash_title">Table de hachage</string>
diff --git a/DroidFishApp/src/main/res/values-it/strings.xml b/DroidFishApp/src/main/res/values-it/strings.xml
index 65a11ae..246bdfc 100644
--- a/DroidFishApp/src/main/res/values-it/strings.xml
+++ b/DroidFishApp/src/main/res/values-it/strings.xml
@@ -50,7 +50,6 @@ Se l\'alimentazione è a batteria, è consigliabile modificare le impostazioni p
     <string name="tools_menu">Strumenti</string>
     <string name="load_save_menu">Apri/Salva partita</string>
     <string name="goto_move">Vai alla mossa</string>
-    <string name="edit_strength">Imposta la Forza del motore</string>
     <string name="edit_randomization">Modifica la casualizzazione</string>
     <string name="invalid_number_format">Formato del numero non valido</string>
     <string name="side_to_move">Lato che muove</string>
@@ -273,8 +272,6 @@ Se l\'alimentazione è a batteria, è consigliabile modificare le impostazioni p
     <string name="prefs_playerNameFlip_title">Gira la scacchiera: Giocatore</string>
     <string name="prefs_playerNameFlip_summary">Usa il nome del giocatore per girare la scacchiera automaticamente</string>
     <string name="prefs_engine_settings">Impostazioni del motore</string>
-    <string name="prefs_strength_title">Forza di gioco</string>
-    <string name="prefs_strength_summary">Supportato solo dai motori interni. La modalità di analisi utilizza sempre la massima forza.</string>
     <string name="prefs_ponderMode_title">Sto riflettendo</string>
     <string name="prefs_ponderMode_summary">Lascia che il motore rifletta nell\'attesa della mossa dell\'avversario. Supportato dalla maggior parte dei motori.</string>
     <string name="prefs_hash_title">Tabella hash</string>
diff --git a/DroidFishApp/src/main/res/values-ko/strings.xml b/DroidFishApp/src/main/res/values-ko/strings.xml
index 2a6bc86..ba22c05 100644
--- a/DroidFishApp/src/main/res/values-ko/strings.xml
+++ b/DroidFishApp/src/main/res/values-ko/strings.xml
@@ -54,7 +54,6 @@ DroidFish는 백그라운드에 실행 중인 상태에서 다음과 같이 설
     <string name="tools_menu">도구</string>
     <string name="load_save_menu">게임 저장/불러오기</string>
     <string name="goto_move">이동으로 가기</string>
-    <string name="edit_strength">강도 조정</string>
     <string name="edit_randomization">랜덤화 편집</string>
     <string name="invalid_number_format">잘못된 숫자 형식</string>
     <string name="side_to_move">이동할 사이드</string>
@@ -277,8 +276,6 @@ DroidFish는 백그라운드에 실행 중인 상태에서 다음과 같이 설
     <string name="prefs_playerNameFlip_title">플립 보드 : 플레이어</string>
     <string name="prefs_playerNameFlip_summary">자동 플립 보드를 위해 플레이어 이름을 사용합니다</string>
     <string name="prefs_engine_settings">엔진 설정</string>
-    <string name="prefs_strength_title">플레이 강도</string>
-    <string name="prefs_strength_summary">내장 엔진에서만 지원합니다. 분석 모드에서는 항상 최고 강도를 사용합니다.</string>
     <string name="prefs_ponderMode_title">숙고하기</string>
     <string name="prefs_ponderMode_summary">상대방의 이동을 기다리는 동안 엔진이 생각하도록 합니다. 대부분의 엔진에 의해 지원됩니다.</string>
     <string name="prefs_hash_title">해시 테이블</string>
diff --git a/DroidFishApp/src/main/res/values-nl/strings.xml b/DroidFishApp/src/main/res/values-nl/strings.xml
index b2f14dc..880f9d4 100644
--- a/DroidFishApp/src/main/res/values-nl/strings.xml
+++ b/DroidFishApp/src/main/res/values-nl/strings.xml
@@ -50,7 +50,6 @@ Als uw telefoon op batterij werkt is het aan te raden om deze instellingen te wi
     <string name="tools_menu">Tools</string>
     <string name="load_save_menu">Laad/Bewaar Partij</string>
     <string name="goto_move">Ga naar zet</string>
-    <string name="edit_strength">Speelsterkte bewerken</string>
     <string name="edit_randomization">Willekeurigheid bewerken</string>
     <string name="invalid_number_format">Ongeldig nummer formaat</string>
     <string name="side_to_move">Speler aan zet</string>
@@ -273,8 +272,6 @@ Als uw telefoon op batterij werkt is het aan te raden om deze instellingen te wi
     <string name="prefs_playerNameFlip_title">Draai bord:Speler</string>
     <string name="prefs_playerNameFlip_summary">Draai bord automatisch op spelers naam</string>
     <string name="prefs_engine_settings">Engine instellingen</string>
-    <string name="prefs_strength_title">Speel sterkte</string>
-    <string name="prefs_strength_summary">Alleen ondersteund door interne engines. Analyse gebruikt altijd de hoogste denksterkte.</string>
     <string name="prefs_ponderMode_title">Peinzen</string>
     <string name="prefs_ponderMode_summary">Laat de engine verder denken tijdens wachten op de zet van de tegenstander.</string>
     <string name="prefs_hash_title">Hashtabel</string>
diff --git a/DroidFishApp/src/main/res/values-pl/strings.xml b/DroidFishApp/src/main/res/values-pl/strings.xml
index 17c852d..03d9860 100644
--- a/DroidFishApp/src/main/res/values-pl/strings.xml
+++ b/DroidFishApp/src/main/res/values-pl/strings.xml
@@ -50,7 +50,6 @@ Jeśli pracujesz na baterii, zalecana jest zmiana ustawień, w celu oszczędzani
     <string name="tools_menu">Narzędzia</string>
     <string name="load_save_menu">Załaduj/zapisz partię</string>
     <string name="goto_move">Idź do posunięcia</string>
-    <string name="edit_strength">Edytuj siłę gry</string>
     <string name="edit_randomization">Zmień losowość</string>
     <string name="invalid_number_format">Niepoprawny format liczby</string>
     <string name="side_to_move">Strona na posunięciu</string>
@@ -273,8 +272,6 @@ Jeśli pracujesz na baterii, zalecana jest zmiana ustawień, w celu oszczędzani
     <string name="prefs_playerNameFlip_title">Obracanie szachownicy: gracz</string>
     <string name="prefs_playerNameFlip_summary">Używaj nazwy gracza, żeby obracać szachownicę automatycznie</string>
     <string name="prefs_engine_settings">Ustawienia silnika</string>
-    <string name="prefs_strength_title">Siła gry</string>
-    <string name="prefs_strength_summary">Wspierane wyłącznie przez lokalne silniki szachowe. Tryb analizy zawsze używa maksymalnej siły gry.</string>
     <string name="prefs_ponderMode_title">Namysł</string>
     <string name="prefs_ponderMode_summary">Silnik szachowy będzie liczył pozycję czekając na posunięcie przeciwnika. Wspierane przez większość silników.</string>
     <string name="prefs_hash_title">Tablica haszująca</string>
diff --git a/DroidFishApp/src/main/res/values-pt/strings.xml b/DroidFishApp/src/main/res/values-pt/strings.xml
index 37ac6fb..106c4ca 100644
--- a/DroidFishApp/src/main/res/values-pt/strings.xml
+++ b/DroidFishApp/src/main/res/values-pt/strings.xml
@@ -50,7 +50,6 @@ Se você está usando somente a bateria, recomenda-se que você mude as configur
     <string name="tools_menu">Ferramentas</string>
     <string name="load_save_menu">Carregar/Salvar partida</string>
     <string name="goto_move">Ir para o lance</string>
-    <string name="edit_strength">Alterar nível</string>
     <string name="edit_randomization">Alterar aleatoriedade</string>
     <string name="invalid_number_format">Formato de número inválido</string>
     <string name="side_to_move">Lado a mover</string>
@@ -273,8 +272,6 @@ Se você está usando somente a bateria, recomenda-se que você mude as configur
     <string name="prefs_playerNameFlip_title">Inverter tabuleiro: jogador</string>
     <string name="prefs_playerNameFlip_summary">Usar o nome do jogador para virar o tabuleiro automaticamente</string>
     <string name="prefs_engine_settings">Configurações do software de Xadrez</string>
-    <string name="prefs_strength_title">Nível de jogo</string>
-    <string name="prefs_strength_summary">Somente suportado pelo software interno. Modo análise sempre usa força total.</string>
     <string name="prefs_ponderMode_title">Análise constante</string>
     <string name="prefs_ponderMode_summary">Deixar o software analisando enquanto espera o lance do oponente. Suportado pela maioria dos softwares.</string>
     <string name="prefs_hash_title">Tabela hash</string>
diff --git a/DroidFishApp/src/main/res/values-ru/strings.xml b/DroidFishApp/src/main/res/values-ru/strings.xml
index 86f7830..69f0465 100644
--- a/DroidFishApp/src/main/res/values-ru/strings.xml
+++ b/DroidFishApp/src/main/res/values-ru/strings.xml
@@ -50,7 +50,6 @@
     <string name="tools_menu">Инструменты</string>
     <string name="load_save_menu">Загрузить/Сохранить партию</string>
     <string name="goto_move">Сделать ход</string>
-    <string name="edit_strength">Изменить уровень сложности</string>
     <string name="edit_randomization">Изменить рандомизацию (случайность)</string>
     <string name="invalid_number_format">Неправильный формат числа</string>
     <string name="side_to_move">Задать направление хода</string>
@@ -273,8 +272,6 @@
     <string name="prefs_playerNameFlip_title">Поворачивать доску: игрок</string>
     <string name="prefs_playerNameFlip_summary">Использовать имя игрока для автоматического поворота доски</string>
     <string name="prefs_engine_settings">Настройки движка</string>
-    <string name="prefs_strength_title">Сила игры</string>
-    <string name="prefs_strength_summary">Поддерживается только внутренними движками. Режим анализа всегда использует полную силу.</string>
     <string name="prefs_ponderMode_title">Размышление</string>
     <string name="prefs_ponderMode_summary">Позволить движку обдумывание во время ожидания хода оппонента. Поддерживается большинством движков.</string>
     <string name="prefs_hash_title">Хэш-таблица</string>
diff --git a/DroidFishApp/src/main/res/values-tr/strings.xml b/DroidFishApp/src/main/res/values-tr/strings.xml
index d991494..f9009ab 100644
--- a/DroidFishApp/src/main/res/values-tr/strings.xml
+++ b/DroidFishApp/src/main/res/values-tr/strings.xml
@@ -50,7 +50,6 @@ Pil gücüyle çalışıyorsanız, pil gücünden tasarruf etmek için ayarları
     <string name="tools_menu">Araçlar</string>
     <string name="load_save_menu">Oyun Yükle/Kaydet</string>
     <string name="goto_move">Harekete git</string>
-    <string name="edit_strength">Gücü ayarla</string>
     <string name="edit_randomization">Rasgeleliği ayarla</string>
     <string name="invalid_number_format">Geçersiz sayı formatı</string>
     <string name="side_to_move">Hareket tarafı</string>
@@ -273,8 +272,6 @@ Pil gücüyle çalışıyorsanız, pil gücünden tasarruf etmek için ayarları
     <string name="prefs_playerNameFlip_title">Tahtayı Dödür: Oyuncu</string>
     <string name="prefs_playerNameFlip_summary">Tahtayı döndürmek için Oyuncu Adını kullan</string>
     <string name="prefs_engine_settings">Motor Ayarları</string>
-    <string name="prefs_strength_title">Oynama zorluğu</string>
-    <string name="prefs_strength_summary">Sadece dahili motorlar destekler. Analiz modu daima tam gücü kullanır.</string>
     <string name="prefs_ponderMode_title">Düşünme</string>
     <string name="prefs_ponderMode_summary">Rakibini beklerken bilgisayarın düşünmesine izin ver. Çoğu motor destekler.</string>
     <string name="prefs_hash_title">Hash Tablosu</string>
diff --git a/DroidFishApp/src/main/res/values-uk/strings.xml b/DroidFishApp/src/main/res/values-uk/strings.xml
index fe34cb8..2893a98 100644
--- a/DroidFishApp/src/main/res/values-uk/strings.xml
+++ b/DroidFishApp/src/main/res/values-uk/strings.xml
@@ -50,7 +50,6 @@
     <string name="tools_menu">Інструменти</string>
     <string name="load_save_menu">Завантажити/Зберегти партію</string>
     <string name="goto_move">Зробити хід</string>
-    <string name="edit_strength">Змінити рівень складності</string>
     <string name="edit_randomization">Змінити рандомізацію (випадковість)</string>
     <string name="invalid_number_format">Неправильний формат числа</string>
     <string name="side_to_move">Задати напрямок ходу</string>
@@ -273,8 +272,6 @@
     <string name="prefs_playerNameFlip_title">Повертати дошку: гравець</string>
     <string name="prefs_playerNameFlip_summary">Використовувати ім\'я гравця для автоматичного повороту дошки</string>
     <string name="prefs_engine_settings">Налаштування рушія</string>
-    <string name="prefs_strength_title">Сила ігри</string>
-    <string name="prefs_strength_summary">Підтримується тільки внутрішніми рушіями. Режим аналізу завжди використовує повну силу.</string>
     <string name="prefs_ponderMode_title">Розважання</string>
     <string name="prefs_ponderMode_summary">Дозволити рушію обдумування під час очікування ходу опонента. Підтримується більшістю рушіїв.</string>
     <string name="prefs_hash_title">Геш-таблиця</string>
diff --git a/DroidFishApp/src/main/res/values-zh-rCN/strings.xml b/DroidFishApp/src/main/res/values-zh-rCN/strings.xml
index 87e6af6..abda69b 100644
--- a/DroidFishApp/src/main/res/values-zh-rCN/strings.xml
+++ b/DroidFishApp/src/main/res/values-zh-rCN/strings.xml
@@ -50,7 +50,6 @@
     <string name="tools_menu">工具</string>
     <string name="load_save_menu">加载/保存对局</string>
     <string name="goto_move">转到着法</string>
-    <string name="edit_strength">编辑棋力</string>
     <string name="edit_randomization">编辑随机性</string>
     <string name="invalid_number_format">编号格式无效</string>
     <string name="side_to_move">轮走棋方</string>
@@ -273,8 +272,6 @@
     <string name="prefs_playerNameFlip_title">翻转棋盘: 棋手</string>
     <string name="prefs_playerNameFlip_summary">以棋手名字自动翻转棋盘</string>
     <string name="prefs_engine_settings">引擎设置</string>
-    <string name="prefs_strength_title">对弈棋力</string>
-    <string name="prefs_strength_summary">支持内置引擎。分析模式总是使用最强棋力</string>
     <string name="prefs_ponderMode_title">思考</string>
     <string name="prefs_ponderMode_summary">引擎在等待对手走棋时思考。支持大多数引擎</string>
     <string name="prefs_hash_title">哈希表</string>
diff --git a/DroidFishApp/src/main/res/values/strings.xml b/DroidFishApp/src/main/res/values/strings.xml
index a30aaad..219608f 100644
--- a/DroidFishApp/src/main/res/values/strings.xml
+++ b/DroidFishApp/src/main/res/values/strings.xml
@@ -50,7 +50,9 @@ If you are running on battery power, it is recommended that you change settings
     <string name="tools_menu">Tools</string>
     <string name="load_save_menu">Load/Save Game</string>
     <string name="goto_move">Goto move</string>
-    <string name="edit_strength">Edit Strength</string>
+    <string name="limit_strength">Limit Strength</string>
+    <string name="set_engine_strength">Set Engine Strength</string>
+    <string name="engine_cannot_reduce_strength">Engine cannot reduce playing strength</string>
     <string name="edit_randomization">Edit Randomization</string>
     <string name="invalid_number_format">Invalid number format</string>
     <string name="side_to_move">Side to Move</string>
@@ -273,8 +275,6 @@ If you are running on battery power, it is recommended that you change settings
     <string name="prefs_playerNameFlip_title">Flip Board: Player</string>
     <string name="prefs_playerNameFlip_summary">Use Player Name to flip board automatically</string>
     <string name="prefs_engine_settings">Engine Settings</string>
-    <string name="prefs_strength_title">Playing Strength</string>
-    <string name="prefs_strength_summary">Only supported by internal engines. Analysis mode always uses full strength.</string>
     <string name="prefs_ponderMode_title">Pondering</string>
     <string name="prefs_ponderMode_summary">Let engine think while waiting for opponent\'s move. Supported by most engines.</string>
     <string name="prefs_hash_title">Hash Table</string>
diff --git a/DroidFishApp/src/main/res/xml/preferences.xml b/DroidFishApp/src/main/res/xml/preferences.xml
index ac9d15f..1881ec8 100644
--- a/DroidFishApp/src/main/res/xml/preferences.xml
+++ b/DroidFishApp/src/main/res/xml/preferences.xml
@@ -30,12 +30,6 @@
     </PreferenceCategory>
     <PreferenceCategory
         android:title="@string/prefs_engine_settings">
-        <org.petero.droidfish.activities.util.SeekBarPreference
-            android:key="strength"
-            android:title="@string/prefs_strength_title"
-            android:summary="@string/prefs_strength_summary"
-            android:defaultValue="1000">
-        </org.petero.droidfish.activities.util.SeekBarPreference>
         <CheckBoxPreference
             android:key="ponderMode"
             android:title="@string/prefs_ponderMode_title"
diff --git a/README.md b/README.md
index efd2edc..08558a6 100644
--- a/README.md
+++ b/README.md
@@ -123,6 +123,29 @@ light bulb image) that toggles analysis mode. When analysis mode is disabled the
 game mode that was used before analysis mode was enabled is restored.
 
 
+# Playing strength
+
+For engines that can reduce their playing strength using the UCI_LimitStrength
+and UCI_Elo options, it is possible to specify the engine playing strength by
+opening the *Left drawer menu* and selecting *Set Engine Strength*. Both
+built-in engines (*Stockfish* and *CuckooChess*) can reduce their playing
+strength.
+
+The available Elo range can be different for different engines. If *Stockfish*
+is playing too strong even on the lowest setting, consider switching to the
+*CuckooChess* engine which is able to play at a much weaker level. At the lowest
+setting, *CuckooChess* plays random legal moves so it should be usable also for
+an absolute beginner.
+
+The selected playing strength is shown in the title bar after the engine name.
+
+Playing strength changes take effect the next time the engine starts to think
+about a move.
+
+The playing strength setting is only used in game playing mode. When the engine
+is in analysis mode, full strength is always used.
+
+
 # The move list text area
 
 The move list keeps a record of moves played during a game and during analysis.
@@ -737,34 +760,6 @@ what to do if a player runs out of time.
 
 Time control changes take effect when a new game is started.
 
-## Playing strength
-
-For built-in engines (*Stockfish* and *CuckooChess*), it is possible to specify
-the playing strength in the *Engine Settings* section. The strength is specified
-as a percentage between 0% and 100%. You can specify the value either by
-dragging the slider, or by tapping the value and entering a new value in the
-dialog box.
-
-For *Stockfish* the actual strength used is an integer value between 0 and 20,
-so the specified percentage value is divided by 5 and rounded down to an
-integer. Even at 0 strength *Stockfish* plays at a level that may be too high
-for a beginner.
-
-For *CuckooChess* the specified percentage value is used without rounding and a
-smaller value causes the engine to make mistakes more often and to make bigger
-mistakes. At 0% strength the engine plays random legal moves so it should be
-usable also for an absolute beginner.
-
-Playing strength changes take effect the next time the engine starts to think
-about a move.
-
-The playing strength setting is only used in game playing mode. When the engine
-is in analysis mode, full strength is always used.
-
-**Note!** For non built-in engines, the *Playing Strength* setting has no
-effect. It may however be possible to set the engine strength by modifying some
-of the engine UCI options.
-
 ## Hash table size
 
 Use *Left drawer menu* -> *Settings* -> *Engine Settings* -> *Hash Table* to
diff --git a/doc/droidfish_manual.pdf b/doc/droidfish_manual.pdf
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