Shredder is available on all platforms and is consistently good. If you are in doubt what chess software to buy then Shredder is probably the one to go for, it has a pleasing interface with a nice chess set, includes the ability to play the computer (of course), it is quite straightforward to enter moves and setup positions, you can analyse then save and e-mail games in .pgn format, and as a big bonus it has a set of tactical problems. All these features makes it a brilliant all-rounder.One minor gripe I have is that the tactics problems award rating points based on solving against the clock, this can be quite fun but often (particularly when I am tired) I want to take my time. You can let the clock run down and take as long as you need, but the competitive side of me hates being awarded zero points – perhaps more mindful meditation is required. This is a very personal gripe and probably not a big concern to most, solving against the clock can be motivating but it does lead to the kind of thinking that makes me such bad blitz player i.e. you see a promising line and in order to stop the countdown tap in the guess without looking for a refutation. One other thing I should mention is that if you move from iPhone/iTouch to iPad you need to pay again for the iPad specific version.
Geek Tip: I discovered recently that when setting up positions in Shredder, if you tap on a piece – say a Knight – when you tap on a square if you keep tapping you can cycle though white knight-black knight-clear square without having to tap back on the piece menu. This greatly speeds up position setup.
Conclusion: I think this a ‘must have’ chess app on Android, and probably for Apple devices as well (there is some competition here particularly tChess/tChesspro which I will be covering soon). The main clincher for Android is the tactics puzzles, as I couldn’t find another Android-based tactics puzzle collection when I looked, whereas there are other offerings on Apple platforms. I bought Shredder for iTouch, iPad and Android and haven’t been disappointed, it looks similar on all platforms and each has the same features as far as I have noticed.