NostalgiaSagaPro is a super fast and full-featured video game emulator to run GameBoy 3DS and Advanced games on the broadest range of Android devices, from very low-end phones to modern tablets. It emulates nearly all aspects of the real hardware correctly..
The emulator can be controlled using external USB/Bluetooth controllers, keyboard, touchscreen or trackball.

This is by far the only emulator that supports link cable emulation with decent speed.