well, its a challenging game and not as intuitive as we hoped. if you're still interested in giving it a try i added a little demo gif in the game page that might help u out with the timing. in any case thanks for playing :)
Gif was a great idea, I watched it, then played again and was able to pass the level! I might suggest that the left arrow is unnecessary as my eyes were glued to the one on the right (as that is the one I'm supposed to match i think). Might be less confusing if you simply hid the left arrow icon/bubble thing. Additionally you could include some pop-up text next to that bubble to indicate success fail, something like too fast or too slow, or Perfect to give user feedback.