From the github description: “A Virtual Boy emulator for the Nintendo 3DS continuing mrdanielps’s work on r3Ddragon, which is itself based on Reality Boy / Red Dragon. It uses a dynamic recompiler with busywait detection and a hardware-accelerated renderer to achieve high performance on the 3DS’s limited hardware.”
I covered this on my own magazine. Let me tell you, it’s really good. Virtual Boy games make a near-perfect transition to the 3DS, and you don’t have to smash your face into a visor for the 3D effects. (You will still get eyestrain, though.) You can, technically, play it on a 2DS, but it’s like drinking non-alcoholic beer… what’s even the point?