It is a rhythm game for Linux, MacOS and Windows + web (for iOS and Android)
The game will feature a built-in song installer, for custom community made songs & maps
Achievements like "100 combo achiever" and "Beatmaker"
The base game will include Standard, Notes, Taiko, Catch, PDiva, Complex Notes and Rhythmatic Switch as gamemodes
Recommended devices may vary, but Drawing Tablets/Touchscreen, Guitar, MIDI Keyboard, Keyboard and Controller are the best options depending on the gamemode
Base languages will start with English & Japanese and support for: German, Spanish and French will be included at a later time
The game is planned to be free (if it's paid it'll be around ~$4.99)

Suggestions are nice to have, and this isn't the only place I'm posting this