This app was mentioned in 7 comments, with an average of 2.00 upvotes
I've used Scid on the go for this. It's got a lot of nice features like
Check out Scid on the go for your Android device. Pair that with games that others have played through that matches your own opening moves so you can see how they won/draw.
No. I PM'd with the original poster (I forget who it was. I would have to look.) of that comment and he uses SCID vs. PC to make the tactics sets, saves them as .pgn files, and uses SCID on the Go in study mode on his tablet to go through the tactics. It's a bit of work, but it has been extremely helpful!
Droidfish is an interface for the Stockfish engine. SF is the absolute king of engines and I doubt you'll find anything stronger. If you're looking for a different interface you could do worse than Scid on the go - I use it for analysis of my games. You could also try Shredder, which supposedly plays in a very "human-like" manner.
Apps I use (I ride the subway every day so they all have to work offline):
If you use Scid on the go for Android as your chess database, it will download PGN files from TWIC!
I use Scid on the go.