Blind Timer, free and nothing to download
The blind timer challenge puts your inner clock to the test: pick a target, tap start and the time disappears. You have to stop it right when you think exactly that many seconds have gone by. Pass the phone around, enter your names and the leaderboard will reveal who has a Swiss watch inside.
Tips and variations
- Raise the target to 30 seconds if 10 feels too easy.
- No counting out loud or tapping your foot: the point is to count in your head.
- Whoever ends up furthest off buys the next round of coffees.