While not all the levels from the PC version is available on iOS, due to screen size restrictions, Ninja vs. Samurai will certainly improve your skills in stealth games. "You're a ninja, trapped in the samurai tower and you're going to have to escape through holes in the floor, avoiding being seen as you go. You have no weapons and no tools, just your ninja skills. Try to make it out alive and take with you any scrolls you may find," pretty much sums up what the game's about. The game is based on the cocos2d engine, and has universal support for iPhone and iPad.