This is clownmdemu, a Sega Mega Drive (a.k.a. Sega Genesis) emulator.

It is currently in the very early stages of development: it can run some games, but many standard features of the Mega Drive are unemulated.

In it's current stage of development it is not the most compatible emulator but has support for gamepad and fullscreen. I was able to play 5 out of 6 random games with no issues.