How well do you focus and concentrate right now?
Designed for self-trackers, this is a quantified self app to let you quickly measure levels of concentration, focus, and attention. Based on the well-known psychological "Stroop Effect", you are presented with a series of randomly-colored cards, which you identify using labels displayed in a randomly-chosen color font. The more cards you can identify in a fixed period of time, the higher your score.
Take the test throughout the day and see if you can spot patterns based on the foods you eat, amount of sleep you had, or other factors.