QGBA/QMedusa
Qt frontend for mGBA.
Code lives mostly on master.
Scripting
Support for scripting languages within mGBA.
Code lives mostly on master.
mGUI
A common UI framework for use in ports to non-GUI platforms, such as the Wii, Vita, and 3DS.
Code lives mostly on master.
Debug Suite
Advanced debugging tools, not all of which are implemented yet.
Code lives mostly on master.
GBA HLE Audio
HLE emulation of Music Player 2000 audio engine, to allow for higher quality mixing.
Code lives at endrift/feature/m4a.
Netplay (mNP)
Netplay support, in progress. Will allow linking between instances over the network, and eventually Orca (Dolphin integration).
Code lives at endrift/feature/np
medusa
Upcoming DS support.
Code lives at mgba-emu/medusa.
Input Revamp
The current input mapping system is clunky and not extensible. It needs to be replaced with a more usable, extensible version.
Code lives at endrift/feature/input-revamp.