Find the circle with a different color than the others.
Each level has 10 games to play and gives you 3 lives, so you can make some mistakes in finding the different color. Making more than 3 wrong selections, will send you back one level! Each game comes with a different color.
Each new level adds more circles and makes it more difficult to find the only circle that has a different color.
There is no limit in levels to reach, the only limit is by the difficulty to select the circle, as they are getting smaller and smaller as you advance in the levels. Bigger screens like iPad or iPhone 6 plus, are allowing more levels.
Have fun and enjoy!