A Little Brain Training

There are several difficulty levels. The very hard stages can take about 10 minutes or more to clear, but you can save your progress and continue later when you reopen the game, which is quite considerate design. If your fingers are thick, you might accidentally hit other arrows and get a false miss, but you have up to 3 misses before it's game over. Of course, you can also continue from where you left off. Since it's not a stamina-based game, even if you make mistakes early on, you can retry as many times as you want, which is also a considerate design. It's a flawless time-killing game.