No need to jailbreak your device.
A Game Boy Advance emulator has been smuggled onto the App Store inside a baby name generator title "Awesome Baby Names", Pocket Gamer reports.
The app costs £1.49 and whilst on the surface appears to be a simple app for suggesting baby names, actually holds an emulating secret.
To access the emulator load up the app, tap on the top-left-hand corner of the screen and then on the middle button found at the bottom of the screen. "Ready Player One" will now appear, which once tapped will bring up a list of Roms.
You'll have previously needed to have loaded some Roms and a GBA bios onto your iDevice into the directory: User_Applications\Awesome\Documents.
Apple is likely to remove the app pretty sharpish so if you want to have a play you'd best download it now. Be warned the emulator isn't actually meant to be much good.
Source: Pocket Gamer