diff --git a/android/res/values/pref_strings.xml b/android/res/values/pref_strings.xml
index f9da2e828..5f3284ac4 100644
--- a/android/res/values/pref_strings.xml
+++ b/android/res/values/pref_strings.xml
@@ -6,6 +6,7 @@
     <string name="PreferenceUseInternalFileBrowserOption">PreferenceUseInternalFileBrowserOpion</string>
     <string name="PreferenceFileBrowserBaseDirectory">PreferenceFileBrowserBaseDirectory</string>
     <string name="PreferenceShowOnlyOrkFiles">PreferenceShowOnlyOrkFiles</string>
+    <string name="PreferenceAutoSaveOption">PreferenceAutoSaveOption</string>
 
     <string-array name="PreferenceMotorBrowserGroupingValues">
         <item>0</item>
diff --git a/android/res/values/strings.xml b/android/res/values/strings.xml
index 074c7a886..81c048b66 100644
--- a/android/res/values/strings.xml
+++ b/android/res/values/strings.xml
@@ -19,6 +19,7 @@
     <string name="loadWarnUnsaved">Would you like to save the changes to the current model?</string>
     <string name="no">No</string>
     <string name="yes">Yes</string>
+    <string name="autoSaveMessage">Automatically saving rocket</string>
 
     <string-array name="PreferenceMotorBrowserGroupingEntries">
         <item>Case</item>
@@ -32,7 +33,12 @@
     <string name="simulationSeries1Label">Series 1</string>
     <string name="simulationSeries2Label">Series 2</string>
 
+    <string name="autosavetitle">Autosave Rocket</string>
+    <string name="autosavesummary">Automatically save the rocket document after simulations</string>
+    
     <string name="motorbrowsergrouptitle">Motor Browser Grouping</string>
+    <string name="motorbrowsergroupsummary">Set the grouping in Motor Browser</string>
+    
     <string name="motorbrowsertitle">Motor Browser</string>
     
     <string name="useinternalfilebrowsertitle">Use Internal File Browser</string>
diff --git a/android/res/xml/preferences.xml b/android/res/xml/preferences.xml
index 7e27894f3..ff39a61f3 100644
--- a/android/res/xml/preferences.xml
+++ b/android/res/xml/preferences.xml
@@ -8,9 +8,15 @@
         android:entries="@array/PreferenceMotorBrowserGroupingEntries"
         android:entryValues="@array/PreferenceMotorBrowserGroupingValues"
         android:key="@string/PreferenceMotorBrowserGroupingOption"
-        android:summary="Set the grouping in Motor Browser"
+        android:summary="@string/motorbrowsergroupsummary"
         android:title="@string/motorbrowsergrouptitle" />
 
+    <CheckBoxPreference
+        android:defaultValue="false"
+        android:title="@string/autosavetitle"
+        android:key="@string/PreferenceAutoSaveOption"
+        android:summary="@string/autosavesummary"/>
+    
     <CheckBoxPreference
         android:defaultValue="true"
         android:title="@string/useinternalfilebrowsertitle"
diff --git a/android/src/net/sf/openrocket/android/rocket/OpenRocketSaverFragment.java b/android/src/net/sf/openrocket/android/rocket/OpenRocketSaverFragment.java
index 5a0b9b31f..6f6745b72 100644
--- a/android/src/net/sf/openrocket/android/rocket/OpenRocketSaverFragment.java
+++ b/android/src/net/sf/openrocket/android/rocket/OpenRocketSaverFragment.java
@@ -12,12 +12,16 @@ import android.support.v4.app.Fragment;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.view.Window;
+
+import com.actionbarsherlock.app.SherlockFragmentActivity;
 
 public class OpenRocketSaverFragment extends Fragment {
 	
-	public static OpenRocketSaverFragment newInstance() {
+	public static OpenRocketSaverFragment newInstance( boolean showProgressDialog) {
 		OpenRocketSaverFragment frag = new OpenRocketSaverFragment();
 		Bundle b = new Bundle();
+		b.putBoolean(SHOW_PRGRESS_DIALOG_ARG, showProgressDialog);
 		frag.setArguments(b);
 		return frag;
 	}
@@ -25,7 +29,10 @@ public class OpenRocketSaverFragment extends Fragment {
 	public interface OnOpenRocketFileSaved {
 		public void onOpenRocketFileSaved( Boolean result );
 	}
+
+	private final static String SHOW_PRGRESS_DIALOG_ARG = "net.sf.openrocket.android.ShowProgressDialog";
 	
+	private boolean showProgressDialog = true;
 	private OpenRocketSaverTask task;
 	private OnOpenRocketFileSaved listener;
 	
@@ -34,6 +41,9 @@ public class OpenRocketSaverFragment extends Fragment {
 		super.onCreate(savedInstanceState);
 		setRetainInstance(true);
 		Bundle b = getArguments();
+		if ( b != null ) {
+			showProgressDialog = b.getBoolean(SHOW_PRGRESS_DIALOG_ARG, true);
+		}
 		if ( task == null ) {
 			// since we retain instance state, task will be non-null if it is already loading.
 			task = new OpenRocketSaverTask();
@@ -63,9 +73,15 @@ public class OpenRocketSaverFragment extends Fragment {
 		@Override
 		protected void onPreExecute() {
 			super.onPreExecute();
-			String savingMessage = getActivity().getResources().getString(R.string.saving);
-			DialogFragment newFragment = ProgressDialogFragment.newInstance("", savingMessage);
-			newFragment.show(getFragmentManager(), PROGRESS_DIALOG_TAG);
+			if ( showProgressDialog ) {
+				String savingMessage = getActivity().getResources().getString(R.string.saving);
+				DialogFragment newFragment = ProgressDialogFragment.newInstance("", savingMessage);
+				newFragment.show(getFragmentManager(), PROGRESS_DIALOG_TAG);
+			} else {
+				((SherlockFragmentActivity)getActivity()).setSupportProgressBarIndeterminate(true);
+				((SherlockFragmentActivity)getActivity()).setSupportProgress(0);
+			}
+			
 		}
 
 		/* (non-Javadoc)
@@ -89,11 +105,16 @@ public class OpenRocketSaverFragment extends Fragment {
 		protected void onPostExecute(Boolean result) {
 			super.onPostExecute(result);
 			AndroidLogWrapper.d(OpenRocketSaverFragment.class,"Finished saving " + OpenRocketSaverTask.this);
-			Fragment progress = getActivity().getSupportFragmentManager().findFragmentByTag(PROGRESS_DIALOG_TAG);
-			if ( progress != null ) {
-				// Remove the fragment instead of trying to use DialogFragment.dismiss.
-				// If the dialog is now currently shown, dismiss fails.
-				getFragmentManager().beginTransaction().remove(progress).commitAllowingStateLoss();
+			if ( showProgressDialog ) {
+				Fragment progress = getActivity().getSupportFragmentManager().findFragmentByTag(PROGRESS_DIALOG_TAG);
+				if ( progress != null ) {
+					// Remove the fragment instead of trying to use DialogFragment.dismiss.
+					// If the dialog is now currently shown, dismiss fails.
+					getFragmentManager().beginTransaction().remove(progress).commitAllowingStateLoss();
+				}
+			} else {
+				((SherlockFragmentActivity)getActivity()).setSupportProgress(Window.PROGRESS_END);
+				((SherlockFragmentActivity)getActivity()).setSupportProgressBarVisibility(false);
 			}
 			if ( listener != null ) {
 				listener.onOpenRocketFileSaved(result);
diff --git a/android/src/net/sf/openrocket/android/rocket/OpenRocketViewer.java b/android/src/net/sf/openrocket/android/rocket/OpenRocketViewer.java
index b04f40eef..c621dab23 100644
--- a/android/src/net/sf/openrocket/android/rocket/OpenRocketViewer.java
+++ b/android/src/net/sf/openrocket/android/rocket/OpenRocketViewer.java
@@ -14,20 +14,25 @@ import net.sf.openrocket.document.Simulation;
 import android.app.AlertDialog;
 import android.content.DialogInterface;
 import android.content.Intent;
+import android.content.SharedPreferences;
+import android.content.res.Resources;
 import android.os.Bundle;
+import android.preference.PreferenceManager;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentManager;
 import android.support.v4.app.FragmentPagerAdapter;
 import android.support.v4.app.FragmentTransaction;
 import android.support.v4.view.ViewPager;
 import android.view.View;
+import android.widget.Toast;
 
 import com.actionbarsherlock.view.Menu;
 import com.actionbarsherlock.view.MenuInflater;
 import com.actionbarsherlock.view.MenuItem;
+import com.actionbarsherlock.view.Window;
 
 public class OpenRocketViewer extends OpenRocketLoaderActivity
-implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnOpenRocketFileSaved
+implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnOpenRocketFileSaved, SharedPreferences.OnSharedPreferenceChangeListener
 {
 
 	private final static int OVERVIEW_POS = 0;
@@ -37,9 +42,11 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 	private final static int TABSIZE = 4;
 
 	private OpenRocketViewerPagerAdapter viewPagerAdapter;
-	
+
 	private final static String LOAD_AFTER_SAVE = "net.sf.openrocket.android.loadAfterSave";
 	private boolean loadAfterSave = false;
+	private String autoSaveEnabledKey;
+	private boolean autoSaveEnabled = false;
 
 	@Override
 	protected void onCreate(Bundle savedInstanceState) {
@@ -58,6 +65,10 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 		if (savedInstanceState != null ) {
 			loadAfterSave = savedInstanceState.getBoolean(LOAD_AFTER_SAVE);
 		}
+		// Must use com.actionbarsherlock.view.Window.FEATURE_INDETERMINATE_PROGRESS
+		requestWindowFeature(Window.FEATURE_PROGRESS);
+		setSupportProgressBarIndeterminate(true);
+
 		setTitle(rocDoc.getRocket().getName());
 		getSupportActionBar().setHomeButtonEnabled(true);
 
@@ -70,11 +81,20 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 	@Override
 	protected void onPause() {
 		CurrentRocketHolder.getCurrentRocket().setHandler(null);
+		SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(this);
+		pref.unregisterOnSharedPreferenceChangeListener(this);
 		super.onPause();
 	}
 
 	@Override
 	protected void onResume() {
+		Resources resources = this.getResources();
+		autoSaveEnabledKey = resources.getString(R.string.PreferenceAutoSaveOption);
+		SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(this);
+		autoSaveEnabled = pref.getBoolean(autoSaveEnabledKey, false);
+
+		pref.registerOnSharedPreferenceChangeListener(this);
+
 		RocketChangedEventHandler handler = new RocketChangedEventHandler();
 		CurrentRocketHolder.getCurrentRocket().setHandler(handler);
 		super.onResume();
@@ -119,9 +139,7 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 					@Override
 					public void onClick(DialogInterface dialog, int which) {
 						OpenRocketViewer.this.loadAfterSave = true;
-						getSupportFragmentManager().beginTransaction()
-						.add( OpenRocketSaverFragment.newInstance(), "saver")
-						.commitAllowingStateLoss();
+						OpenRocketViewer.this.saveRocketDocument();
 					}
 				});
 				builder.create().show();
@@ -130,9 +148,7 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 			}
 			return true;
 		case R.id.menu_save:
-			getSupportFragmentManager().beginTransaction()
-			.add( OpenRocketSaverFragment.newInstance(), "saver")
-			.commitAllowingStateLoss();
+			OpenRocketViewer.this.saveRocketDocument();
 			return true;
 		case android.R.id.home:
 			ActivityHelpers.goHome(this);
@@ -150,6 +166,13 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 		return super.onMenuItemSelected(featureId, item);
 	}
 
+	@Override
+	public void onSharedPreferenceChanged(SharedPreferences arg0, String arg1) {
+		if ( autoSaveEnabledKey.equals(arg1) ) {
+			autoSaveEnabled = arg0.getBoolean(autoSaveEnabledKey, false);
+		}
+	}
+
 	@Override
 	public void onSimulationSelected(int simulationId) {
 
@@ -185,6 +208,12 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 		}
 	}
 
+	private void saveRocketDocument() {
+		getSupportFragmentManager().beginTransaction()
+		.add( OpenRocketSaverFragment.newInstance(false), "saver")
+		.commitAllowingStateLoss();
+	}
+
 	@Override
 	public void onOpenRocketFileSaved(Boolean result) {
 		invalidateOptionsMenu();
@@ -198,6 +227,10 @@ implements Simulations.OnSimulationSelectedListener, OpenRocketSaverFragment.OnO
 
 		@Override
 		protected void doSimsChanged() {
+			if ( autoSaveEnabled ) {
+				Toast.makeText(OpenRocketViewer.this, R.string.autoSaveMessage, Toast.LENGTH_SHORT).show();
+				OpenRocketViewer.this.saveRocketDocument();
+			}
 			invalidateOptionsMenu();
 			Simulations sims = (Simulations) viewPagerAdapter.getFragmentAtPos(SIMS_POS);
 			if ( sims != null ) {