A free app for Android, by John emulators.
John GBAC is a GBA/GBC emulator for Android.
It allows you to play GBA and GBC games on your device.
The original GBA/GBC engine is used, which gives you a high quality rendering for a smooth gaming experience.
You can search for game files in the internal storage or the SD card.
You can also have a virtual on-screen keypad. There is an option to customize the layout, with the option to hide the buttons and labels.
There is an option to enable the zipped file support.