Gearboy is a Nintendo GameBoy and GameBoy Color emulator written in C++. This emulator was developed by Ignacio Sanchez (aka DrHelius), an indie game developer and full time Software Architect, with the main focus being the readability of the source code with high compatibility. Several versions of GearBoy can be played on numerous devices such as Windows, Mac, Raspberry Pi and Linux. The iOS version can be found for both jailbreak and non-jailbreak devices.
Gearboy supports all versions of iPad, iPhone, iPod touch running iOS 5.1 and above; this includes iPhone 5 and other retina enabled devices. The emulator automatically saves your progress every time you change games and when you quit, no action needed. Gearboy requires ROM images to play and no ROMs are included. If you own any games, add them through iTunes Sharing.
The developer originally intended to sell Gearboy through Cydia and he accomplished as much; however, only hours later, the app was taken down due to some issues on PayPal's part. A week later, Ignacio decided to forget about making money with it and distribute Gearboy for free.