Wait for green, then tap as fast as you can. Five taps, about twenty seconds.
Touchscreens add about 50 to 100 ms of their own delay, so the same person reads faster on a PC.
For a simple visual stimulus, most adults land between 200 and 280 milliseconds with a mouse. A touchscreen adds roughly 50 to 100 milliseconds of its own latency, so phone results read a little slower than the same person on a PC. Under 220 ms on a phone is fast.
One tap is luck. Five taps with a random wait before each one gives an average that means something and a best that shows your ceiling. Tapping before the screen turns green does not count and restarts that attempt.
No. Reaction time is one ingredient. Aim is reaction plus precision, tracking and target switching with a mouse, which is what the full AimBetween trainer measures on a PC. This test is the phone-sized taste of it. The reaction time guide covers what is normal and how to improve it.