1. Packages: there are two concepts of "package" on Android. Here's a great overview. Make a new Android application package for each project, don't change them if you can avoid it. In my case, I had originally started on my current project, "How are you right now?" with the package com.dantasse, but that leads to two problems:
- I couldn't install multiple apps with the Android application package com.dantasse on the same phone at the same time
- I couldn't publish multiple apps with the Android application package com.dantasse in the Android market at the same time.
2. Android internal storage: it's pretty opaque. The official Android docs are pretty good at telling you how to access both internal storage (on the phone itself) and external storage (SD card). Internal storage is easy to use, but AFAICT it's not viewable via the standard filesystem. (I read somewhere that it goes in /data/data/(your app) , but I tried using Astro file manager to browse through it on the phone and couldn't find it. And I wasn't able to mount the internal data on a computer, just the SD card.)
There might be something you can do with content providers or something to get this internal data out of your app, but I don't know it.