A number of games have been created directly for the Fruit Jam in CircuitPython -- no emulator necessary. Check out Snak, Minesweeper, Chip's Challenge, Larsio Paint Music, and others.

The beauty of running games directly on Fruit Jam

Unlike an emulator, which tries to "fool" a program or game made for another hardware platform to run on Fruit Jam, these games were written specifically to work on Fruit Jam directly.

Most of the games are written in CircuitPython and are open source. This means you can go into the source code and change things to suit your style. For breakout, there are variables for ball speed, points, and more you can change to make the game easier, harder, or more fun.