Link: https://github.com/trekawek/coffee-gb/releases/tag/coffee-gb-1.7.4

Gameboy emulator in Java and Kotlin. Contribute to trekawek/coffee-gb development by creating an account on GitHub.

• Datel: boot the game through an Action Replay Online (#66) in #92
• Emulate the CGB infrared port and the Full Changer (#94) in #95
• Emulate the MBC5 rumble motor (#93) in #96
• Game-controller support via SDL2 (#78) in #97
• Find system SDL2 on macOS so game controllers work there (#78) in #98
• Add Daid test suite support and plain ROM+RAM handling in #110
• Add integration ROM test suites and related fixtures in #115
• Add MBC30 banking support in #116
• Fix BullyGB hardware checks in #118
• Fix MBC3 real-time clock behavior in #119
• Add CGB Acid test to CI in #121
• Fix SameSuite hardware timing in #128
• Fix Joust & Defender trainer screen in #129
• Support BHGOS multicart banking in #130
• Blank the first DMG frame after LCD enable in #132
• Fix SGB transfer capture timing in #134
• Integrate mooneye-wilbertpol suite in #138
• Support Bung EMS mapper for Cube Raider in #141
• Show the Crazy Castle 3 trainer in #140
• Fix Bo Jackson scoreboard rendering in #142
• Fix Bomberman Collection SGB graphics in #143
• Parallelize integration test profiles and CI in #153
• Emulate MainBlow Bung flashcart RAM in #152
• Fix Initial D Gaiden STAT interrupt lockup in #150

Interesting, an emulator distributed as a Java binary. Also if I remember correctly from the time I did programming, Kotlin would make it specially possible to port to Android, no?

Not sure. Android programming uses Kotlin but android is also very different. Back when Android Java porting a Java program to Android was required a lot of work.