Sega may have axed the fan-made remake of Streets of Rage 2 recently, but redemption comes in the form of the original classic arriving on iOS for iPhone.
Similar to Sega's many other iPhone ports, it uses on-screen controls that are large enough to actually work pretty well. It also dons wireless multiplayer via Bluetooth, although you'll need 3rd generation iPhone & iPod touch and 3.x OS or better.
In what we think is a cool added extra, it also comes with original Japanese version of the game, titled Bare Knuckle 2, included. To access it you just have to change your phone's language to Japanese (but don't forget how to change it back).