Testing your reaction time on a phone

A reaction test shows a signal and measures how long you take to respond. On a phone, the signal can be a colour change, a sound or a vibration, and the response can be a tap or a movement.

Three kinds of test

• Tap tests. The screen turns green, you tap. Measures eyes → finger.
• Sound tests. A beep, you tap. Hearing tends to be slightly faster than sight.
• Motion tests. A signal, you move the phone. Measures eyes or ears → whole arm.

Cowboy Duel (my game) is a motion test. You hold the phone vertically like a holstered revolver, wait for “FLIP!”, then whip it horizontal. The phone’s motion sensors record the moment you move. Times in Cowboy Duel include moving your arm, so they run slower than a click test and aren’t comparable with one.

What skews the number

• Hardware: screen refresh rate and touch sampling.
• Guessing: jumping early. Cowboy Duel catches false starts.
• Fatigue and warm-up: your first few tries are usually slower.

Getting a fair reading

1. Sit or stand the same way each time.
2. Do five warm-up rounds, then count the next ten.
3. Look at your average and your best, not one lucky run.
4. Compare with yourself on the same phone.

Great

The game is overall great. It feels like an actual duel. The only problem is is that my phone doesn’t pick up the flip about a half second later

★★★★★ App Store review, United States, 4 June 2026, _Axyx_ · App Store

That half second is worth explaining. Motion detection needs a clear movement past a threshold; a slow, hesitant flip registers later than a sharp one.

Next: what is a good reaction time?