Help needed finding an ipod touch rail shooter...

[dave4shmups]

Four years ago, after a church service, this friend of mine showed me a rail shooter that he had on his ipod touch. I can't remember the name of it, and neither can he, but you control a gun turret with two rotating machine guns on it, and just shoot at enemies. Kind of like Incoming, except without the vehicle levels, and with a different graphical style. I have an ipad air, so if anyone remembers the name of this game, please respond.