Less than a quarter of a second. That's all the time you have to count how many dots are on the screen. A surprisingly challenging and addictive game.
The human brain has the ability to identify how many objects are in a small set without actually counting them. This is called subitizing (http://en.wikipedia.org/wiki/Subitizing), and could be a factor in mathematical ability. When you play Count the Dots, you will find yourself using this skill to identify the number of dots on the screen without actually having the time to count them.