Holy peripheral device, Batman!
The device is designed to work with your smartphone and an emulating software. However, the device also makes steps towards remedying the issue of legality around ROMs by necessitating the use of an actual game cartridge as well.
The Smart Boy is going into production after a successful online campaign to determine interest, as well as a fruitful unveiling at E3. There is no release date yet slated, but it is certainly a piece of tech worth keeping an eye on.