DreamGBA is a GBA emulator that was created by the same team that wrote the GBC Emulator DreamGBC. The emulator has sadly been out of development for a long time now, but it did suffer from some big down sides. It was originally somewhat promising, being able to successfully run several different games such as Castlevania and Tactics Ogre. This was alongside also being able to successfully emulate there sound, a bit of a feat at the time of DreamGBA’s creation.
However though, as said earlier, DreamGBA suffered from a rather large issue, and this is that it required the GBA Bios to be able to run It is a feature that ended up damaging DreamGBA’s prospects in the long run as obtaining the GBA bios from a console back then was not a simple task.
Even now most legal sites won’t distribute the GBA bios as it is copyrighted material by Nintendo, however a quick google search will quickly find you the GBA bios. However there are now much better emulators available, all that don’t require the usage of the GBA bios.