diff --git a/DroidFish/res/values/strings.xml b/DroidFish/res/values/strings.xml
index 1bb2033..9f2dbbd 100644
--- a/DroidFish/res/values/strings.xml
+++ b/DroidFish/res/values/strings.xml
@@ -76,6 +76,7 @@ you are not actively using the program.\
     <string name="edit_move_counters">Edit Move Counters</string>
     <string name="internal_book">&lt;Internal Book&gt;</string>
     <string name="eco_book">&lt;ECO Book&gt;</string>
+    <string name="no_book">&lt;No Book&gt;</string>
     <string name="select_opening_book_file">Select opening book file</string>
     <string name="select_chess_engine">Select Chess Engine</string>
     <string name="select_pgn_file">Open PGN file</string>
diff --git a/DroidFish/src/org/petero/droidfish/DroidFish.java b/DroidFish/src/org/petero/droidfish/DroidFish.java
index a5a1b46..09f7678 100644
--- a/DroidFish/src/org/petero/droidfish/DroidFish.java
+++ b/DroidFish/src/org/petero/droidfish/DroidFish.java
@@ -1472,7 +1472,7 @@ public class DroidFish extends Activity
         BookOptions options = new BookOptions(bookOptions);
         if (options.filename.isEmpty())
             options.filename = "internal:";
-        if (!options.filename.equals("internal:") && !options.filename.equals("eco:")) {
+        if (!options.filename.endsWith(":")) {
             String sep = File.separator;
             if (!options.filename.startsWith(sep)) {
                 File extDir = Environment.getExternalStorageDirectory();
@@ -2512,13 +2512,17 @@ public class DroidFish extends Activity
             }
         });
         final int numFiles = fileNames.length;
-        CharSequence[] items = new CharSequence[numFiles + 2];
+        final CharSequence[] items = new CharSequence[numFiles + 3];
         for (int i = 0; i < numFiles; i++)
             items[i] = fileNames[i];
         items[numFiles] = getString(R.string.internal_book);
         items[numFiles + 1] = getString(R.string.eco_book);
-        final CharSequence[] finalItems = items;
-        int defaultItem = bookOptions.filename.equals("eco:") ? numFiles + 1 : numFiles;
+        items[numFiles + 2] = getString(R.string.no_book);
+        int defaultItem = numFiles;
+        if (bookOptions.filename.equals("eco:"))
+            defaultItem = numFiles + 1;
+        else if (bookOptions.filename.equals("nobook:"))
+            defaultItem = numFiles + 2;
         for (int i = 0; i < numFiles; i++) {
             if (bookOptions.filename.equals(items[i])) {
                 defaultItem = i;
@@ -2535,8 +2539,10 @@ public class DroidFish extends Activity
                     bookFile = "internal:";
                 else if (item == numFiles + 1)
                     bookFile = "eco:";
+                else if (item == numFiles + 2)
+                    bookFile = "nobook:";
                 else
-                    bookFile = finalItems[item].toString();
+                    bookFile = items[item].toString();
                 editor.putString("bookFile", bookFile);
                 editor.commit();
                 bookOptions.filename = bookFile;
@@ -2707,14 +2713,13 @@ public class DroidFish extends Activity
                 break;
             }
         }
-        CharSequence[] items = new CharSequence[numFiles + 1];
+        final CharSequence[] items = new CharSequence[numFiles + 1];
         for (int i = 0; i < numFiles; i++)
             items[i] = fileNames[i];
         items[numFiles] = getString(R.string.new_file);
-        final CharSequence[] finalItems = items;
         AlertDialog.Builder builder = new AlertDialog.Builder(this);
         builder.setTitle(R.string.select_pgn_file_save);
-        builder.setSingleChoiceItems(finalItems, defaultItem, new DialogInterface.OnClickListener() {
+        builder.setSingleChoiceItems(items, defaultItem, new DialogInterface.OnClickListener() {
             public void onClick(DialogInterface dialog, int item) {
                 String pgnFile;
                 if (item >= numFiles) {
diff --git a/DroidFish/src/org/petero/droidfish/book/DroidBook.java b/DroidFish/src/org/petero/droidfish/book/DroidBook.java
index 6b49145..359fa42 100644
--- a/DroidFish/src/org/petero/droidfish/book/DroidBook.java
+++ b/DroidFish/src/org/petero/droidfish/book/DroidBook.java
@@ -53,6 +53,7 @@ public final class DroidBook {
     private IOpeningBook externalBook = new NullBook();
     private IOpeningBook ecoBook = new EcoBook();
     private IOpeningBook internalBook = new InternalBook();
+    private IOpeningBook noBook = new NoBook();
     private BookOptions options = null;
 
     private static final DroidBook INSTANCE = new DroidBook();
@@ -78,6 +79,7 @@ public final class DroidBook {
         externalBook.setOptions(options);
         ecoBook.setOptions(options);
         internalBook.setOptions(options);
+        noBook.setOptions(options);
     }
 
     /** Return a random book move for a position, or null if out of book. */
@@ -179,6 +181,8 @@ public final class DroidBook {
             return externalBook;
         } else if (ecoBook.enabled()) {
             return ecoBook;
+        } else if (noBook.enabled()) {
+            return noBook;
         } else {
             return internalBook;
         }
diff --git a/DroidFish/src/org/petero/droidfish/book/NoBook.java b/DroidFish/src/org/petero/droidfish/book/NoBook.java
new file mode 100644
index 0000000..028650f
--- /dev/null
+++ b/DroidFish/src/org/petero/droidfish/book/NoBook.java
@@ -0,0 +1,43 @@
+/*
+    DroidFish - An Android chess program.
+    Copyright (C) 2017  Peter Österlund, peterosterlund2@gmail.com
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package org.petero.droidfish.book;
+
+import java.util.ArrayList;
+
+import org.petero.droidfish.book.DroidBook.BookEntry;
+import org.petero.droidfish.gamelogic.Position;
+
+class NoBook implements IOpeningBook {
+    private boolean enabled = false;
+
+    @Override
+    public boolean enabled() {
+        return enabled;
+    }
+
+    @Override
+    public void setOptions(BookOptions options) {
+        enabled = options.filename.equals("nobook:");
+    }
+
+    @Override
+    public ArrayList<BookEntry> getBookEntries(Position pos) {
+        return null;
+    }
+}
diff --git a/DroidFish/src/org/petero/droidfish/book/NullBook.java b/DroidFish/src/org/petero/droidfish/book/NullBook.java
index 0cd026c..3903a1f 100644
--- a/DroidFish/src/org/petero/droidfish/book/NullBook.java
+++ b/DroidFish/src/org/petero/droidfish/book/NullBook.java
@@ -31,11 +31,11 @@ class NullBook implements IOpeningBook {
     }
 
     @Override
-    public ArrayList<BookEntry> getBookEntries(Position pos) {
-        return null;
+    public void setOptions(BookOptions options) {
     }
 
     @Override
-    public void setOptions(BookOptions options) {
+    public ArrayList<BookEntry> getBookEntries(Position pos) {
+        return null;
     }
 }