The latest edition of iPhone Gems focuses mostly on five noteworthy games from the past week, but we also look at a couple of unusual new applications that aren’t easy to categorize. What’s worth your attention? Check out Aki Mahjong and Break Classic, then skip over to Koi Pond unless the other titles really grab your attention. Aki Mahjong, Revisited Though we’re not going to do this often, or even more than once in a great while,…