If you already played on standard Dolphin and want to switch:

Your saves, config, and shader caches will carry over.

Your Dolphin-MMJR-Portable folder will contain:

Dolphin-MMJR-Portable/
├── Config/          # All emulator settings (graphics, controllers, etc.)
├── Cache/           # Shader caches (improves performance)
├── GameSettings/    # Per-game config files (e.g., SMG.ini)
├── GC/              # GameCube memory cards (MemoryCardA.USA.raw)
├── Wii/             # Wii NAND, saves, and system menu files
├── Load/            # Custom textures or cheats
├── Logs/            # Debug logs
├── portable.txt     # The flag file (do not delete)
└── (your ROMs can go here, but better to keep separate)

Because this is a community fork, it is not on the Google Play Store. You must sideload it. Disclaimer: Emulation is legal; downloading ROMs of games you do not own is not. This guide assumes you are using legally obtained backups of your own games.

This is the killer feature. In mainline Dolphin, this setting often breaks games. In MMJR 11505, it is optimized to provide a massive speed boost in titles like The Legend of Zelda: The Wind Waker and Super Mario Sunshine without crashing.