Hi Claire, this game is fascinating! All the assets and music match so well. Even the font and low-saturated colors create a kind of mysterious atmosphere. I agree with most of the other comments that this game is definitely visually pleasing. Besides, the mechanics are simple and easy to understand. When I press "SPACE" for the first time, I already know the only movement of the game. In one second, I'm about to know the whole mechanics of your game. I think your game really made a successful introduction to its players!
The only things I could think of and which could make it better are adding a second stage and making different-sized red and blue parts on the ring. Sometimes, I feel it's hard to rotate when "enemies" are approaching from four directions. Maybe you can make only one "enemy" coming in the first stage, then two in the second stage and so on. Overall, this seems to be a very completed mobile game! Nice jobs!