I would also make sure you had some sort of error reporting so you know how many users are encountering error's. You may want to keep a copy of your old version when updating your app incase you need to roll back. Its also nice to compile a checklist specific for your app that you can go over everytime.
Also to add to this you may want to use a trimmer to take pieces of code out that are unused to cut down on the overall file size(as phone space is pretty limited). You also may want to obfuscate your code for extra protection.
