I'm building an android app that provides several interactive adventures to the user. These use a lot of media (sound files and images, plus some xml), and therefore a lot of space.
I'm planning on a freemium model where the app is downloaded free with one adventure, and the user can buy more from Google Play.
What I'm wondering is:
1) How do I structure my app so as not to blow 50mb apk?
2) Does internal storage have a size limit?
3) The in-app billing examples I've seen all assume that it's for something trivial that's already in the app. How do I set it up so that an adventure is downloaded when it's purchased?