Earlier this year, I
started a thread about my experiences with some different Bible apps for Android and several other MR folks added their thoughts.
A half-year later and Tecarta is still my favorite, all things considered. I'd still like a wider breadth of resources to be available, but I mostly use the app for verse lookups and searches, so having other resources as regular ebooks isn't too big of an inconvenience. I check every so often to see if any promising new apps appear and I haven't seen anything worthy of note in the meantime.
Edit: One thing I just thought of is that when you buy one of the study Bibles, you get the corresponding Bible text along with it. If you plan to buy the NIV Study Bible, for example, you get the same NIV Bible that is otherwise available for sale (and you don't get a price break or anything if you already
have the NIV).