Touch the three circles at the same time to gain one point. Repeat until the time is up. Every ten points you earn five extra seconds. Get as far as you can. That's all.
This second early short test shows the timer and counter tested. During testing I was wondering how the high score could be formed - initially I simply thought that you have a number of solves to make and the time is the high score. However, I would get same times most runs, so it wasn't exactly fun.
I also noticed then that playing with a time is also quite boring since it would need great effort by the player to be just 2-3 solves better - and it wouldn't be more interesting either...
I then however added a rule that gave the game a nice twist: Ever 10 solves you'd get 5 extra seconds. That means that if you are able to make one solve every 500ms, you could play infinitely. This little rule caued me to get very different scores depending on my playing quality.
It also adds a reward to the game for a good round, so it's motivating to improve the play speed.