diff --git a/app/android/jni/RTABMapApp.cpp b/app/android/jni/RTABMapApp.cpp
index 1f700853..686d12a5 100644
--- a/app/android/jni/RTABMapApp.cpp
+++ b/app/android/jni/RTABMapApp.cpp
@@ -2020,8 +2020,10 @@ void RTABMapApp::save(const std::string & databasePath)
 		dataRecorderMode_ = dataRecorderModeBackup;
 	}
 
+	std::map<int, rtabmap::Transform> poses = rtabmap_->getLocalOptimizedPoses();
 	rtabmap_->close(true, databasePath);
 	rtabmap_->init(getRtabmapParameters(), dataRecorderMode_?"":databasePath);
+	rtabmap_->setOptimizedPoses(poses);
 	if(dataRecorderMode_)
 	{
 		clearSceneOnNextRender_ = true;
@@ -2057,6 +2059,13 @@ bool RTABMapApp::exportMesh(
 	// make sure createdMeshes_ is not modified while exporting! We don't
 	// lock the meshesMutex_ because we want to continue rendering.
 
+	std::map<int, rtabmap::Transform> poses = rtabmap_->getLocalOptimizedPoses();
+	if(poses.empty())
+	{
+		UERROR("Empty optimized poses!");
+		return false;
+	}
+
 	if(blockRendering)
 	{
 		renderingMutex_.lock();
@@ -2069,8 +2078,6 @@ bool RTABMapApp::exportMesh(
 
 	try
 	{
-		std::map<int, rtabmap::Transform> poses = rtabmap_->getLocalOptimizedPoses();
-
 		int totalSteps = 0;
 		totalSteps+=poses.size(); // assemble
 		if(meshing)
@@ -2373,6 +2380,10 @@ bool RTABMapApp::exportMesh(
 							}
 						}
 					}
+					else
+					{
+						UERROR("Merged cloud too small (%d points) to create polygons!", (int)mergedClouds->size());
+					}
 				}
 				else // organized meshes
 				{
@@ -2736,6 +2747,10 @@ bool RTABMapApp::exportMesh(
 					success = true;
 				}
 			}
+			else
+			{
+				UERROR("Merged cloud is empty!");
+			}
 		}
 
 		progressionStatus_.finish();
diff --git a/app/android/src/com/introlab/rtabmap/RTABMapActivity.java b/app/android/src/com/introlab/rtabmap/RTABMapActivity.java
index d40e49b0..385e3097 100644
--- a/app/android/src/com/introlab/rtabmap/RTABMapActivity.java
+++ b/app/android/src/com/introlab/rtabmap/RTABMapActivity.java
@@ -2128,7 +2128,7 @@ public class RTABMapActivity extends Activity implements OnClickListener, OnItem
 							}
 							else
 							{
-								updateState(State.STATE_IDLE);
+								updateState(previousState);
 								mToast.makeText(getActivity(), String.format("Exporting map failed!"), mToast.LENGTH_LONG).show();
 							}
 							mExportProgressDialog.dismiss();
@@ -2159,6 +2159,7 @@ public class RTABMapActivity extends Activity implements OnClickListener, OnItem
 			mProgressDialog.setMessage(String.format("Please wait while saving \"%s\"...", newDatabasePathHuman));
 		}
 		mProgressDialog.show();
+		final State previousState = mState;
 		updateState(State.STATE_PROCESSING);
 		Thread saveThread = new Thread(new Runnable() {
 			public void run() {
@@ -2197,7 +2198,7 @@ public class RTABMapActivity extends Activity implements OnClickListener, OnItem
 							mOpenedDatabasePath = newDatabasePath;
 						}
 						mProgressDialog.dismiss();
-						updateState(State.STATE_IDLE);
+						updateState(previousState);
 					}
 				});
 			}