


No gameplay problem, experience somewhat degraded but 100% playable.
Mouse control needs to be resetted between each song by switching to other window (sometime twice) to have full control over 1920x1080 screen.
Certain in game fonts are thin/condensed, but still legible.
Steam Cloud not supported. It may be possible to transfer saves manual from device to Steam Deck. Symphony uses an online account to track leaderboard scores. To be fair, game was designed to work with your local game library, but after signing in, I don't think the game shown my previous score for Electric Love.
Works practically out of the box for Steam Deck. Developer posts on the forum mention added Controller support, but at minimum, the mouse is still needed for menus. Community/Custom Layouts will solve this problem, making Symphony a perfect game for Steam Deck if you have music accessible by the device.

After remapping controls the game runs beautifully and supports importing your tracks as well
Custom layout
- Both trackpads As Mouse (left), left trackpad click as Left Mouse Click (toggleable)
- Both triggers as Left Mouse Click
- Left joystick as Scroll Wheel Up/Down, Right joystick touch as gyro activator
Mouse gets stuck in incorrect boundaries in the menus but quickly moving the mouse to opposite edges helps
Aside from the mouse getting stuck everything else works fine