Test your reaction speed. Tap the moment the screen turns green and beat your best time in milliseconds.
Tap the screen to start.
Wait for the screen to turn green, then tap as fast as you can.
If you tap too early (while red), you lose the round. Lower time is better.
Reaction time is mostly about your starting posture, not raw reflexes. Rest your thumb lightly on the glass so it is already touching the screen — the instant green appears you only need a tiny press, not a full swing of the arm. Keep your gaze soft and fixed on the centre of the screen rather than darting around, because peripheral vision actually registers a full-screen colour change faster than a hard stare does.
The biggest score killer is anticipation. The green flash arrives after a random delay, so trying to guess the exact moment leads to early taps that void the round. Treat every round as if green could come a beat later than you expect and let the colour trigger your finger, not your prediction. A clean 200–250 ms is a strong human result; anything under 180 ms usually means you jumped early.