It supports all of the things you’d expect from a frontend (savestate management, pausing, screenshots, etc.).
m64p uses mupen64plus-gui, a brand new mupen64plus frontend written in Qt5. Available for Windows, Mac, and Linux Download Emulator. Once you’ve downloaded the AltStore, you can use the Delta emulator to play all of the best Gameboy games and all of your favourite N64 games… Apple doesn’t produce their own emulators, but the AltStore is an app you can download with your own Apple ID, so it’s perfectly legit and doesn’t undermine any Apple policies.