Android - restore last viewed Activity

Question

I have 3 different Activities that user navigates between in no particular order. My goal it twofold:

1. When user switches to something else when app is resumed

Answer 1

I believe you want to implement onSaveInstanceState and that will store your activities current state in a bundle. That bundle will be passed into your activity in onCreate, and you can use it to reset your values.

http://developer.android.com/guide/topics/fundamentals.html#actstate