Sorry, but there aren't any right now. If you google around, the only ones you will see are hoaxes/fake because at the moment it's almost impossible to make an emulator on them. They came out only a few years ago so the going is tough, but they might be out some day.
Yeah those exist. Desmume is the best for GBA and DS.
The rest just suck, have bad UI and whatever. Desmume is just the most convenient, doesn't have much lag, and is easy to use and just has a good system in general. Saving is also very convenient.