Hi,
I think I solved the problem by moving my source PNG files to different location where it loads the files faster. Anyways, I'm sorry for posting a question that is not related to ArcGIS Mobile. I thought ArcGIS Mobile generally meant any ArcGIS apps running on smartphones. I will post any questions regarding ArcGIS App for Andriod or Apple on "ArcGIS for Smartphones/Tablets App" forum from now on.
Thank you.
