I downloaded a free chess puzzle app (just called "Chess Problems") for my iPhone a while ago, and it seems to be pretty good. It has over 100 puzzles of varying difficulty, including direct mates, helpmates, and selfmates. Just wanted to let you guys know.
Here are two of my favorite "Mate in 2's" from the easy level:
Yes, I have the same app and find it really good. The big drawback though is: the solutions aren't given! I've struggled through all of the most straightforward puzzles on my own steam, but am stuck with the selfmate puzzles at the difficult levels - can anyone recommend an app to help here?