You play (or rather control) a short line (a rather abstract identifier for some spaceship thingy) that can change color by executing a certain action (fly up, fall down, spin around). This is needed to get past color coded barriers. Only if you have the same color as the barrier you can pass, otherwise you’ll die. There are eight levels, each is increasingly harder to beat, each introducing new gameplay elements.
Flywrench can easily become frustrating, especially because the gameplay is so addictive that you’ll play the level where you are stuck presently again and again until you’ve beaten it. Reminds me a bit of the Jumper series, not the gameplay, but the difficulty. The game is never unfair, everything you need to beat a level is right before your eyes, you just have to control your flywrench perfectly (which is not very easy to do, the controls are extremely sensitive, the only counterpoint to a well done game).
Despite having rather minimalistic graphics, everything looks very well done and very stylish. I even like the atonal soundscape. Overall, neat game.