Pretty cool game, one thing I'd suggest is making it more clear when you need a gem to keep flying, there didn't seem to be an indicator of that anywhere.
Viewing post in SpinSync jam comments
There is one line in the very bottom of the screen, but it's not very visible and it blends with the background a bit. Also the ship booster dims when you're energy goes low, but it's not obvious enough either, understandably you missed them. I should fix the line color to be of a more vibrant color at least. I hope you enjoyed the experience anyway, thanks for playing!