The sample chat app code available through code generation has a minor problem. The app crashes if the device screen is rotated. It happens because of the progress dialog. An AsyncCallback solves the problem.
Hi Arka!
Thank you for this correction.
We will change it.
Regards,
Kate.
You are welcome. 
I think a simpler solution would be to keep the same configuration on rotation. Adding this to the manifest file solves it - android:configChanges=“orientation|screenSize”