via http://www.aep-emu.de/
Marat Fayzullin has ported his (commercial) GameBoy Advance emulator VGBA to the Android platform: VGBA for Android

Quote:
New in 3.8.13:
* Fixed Granite Cave level in Pokemon games.
* Fixed failures to load state files when FlashROM/EEPROM size
changes.
* Fixed "normal" (non-persistent) fast-forwarding function.
* Made user-assigned key mappings override default key mappings.
* Xperia Play [X] button now acts as FIRE-A (was START before).