Sencha Touch - First experiences

I've build my first application with Sencha Touch 2.4.1 using Sencha Architect 3.2 and after two days the software is at least doing something. What I found out for me:

-> Galaxy S1 Android 2.3.3 Gingerbread. The application is not loading at all. The default loading animation is runing and running and running and nothing happened. This happens on all my Gingerbread phones.

-> Galaxy S4 mini (Android 4.4.2), application is loading and running - but images in a carousel are not showing up. The requests to get the images are not done.

-> Samsung Tab7 (Android 4.1.7) - everything is running

-> Samsung Tab 10.1 (Android 4.1.2) - working slow but ok

-> Samsung Tab 12.x - everything is running

It seems to be a long way to get a stable program on lots of devices ...

Sencha Touch - First experiences