Stroop Effect Experiment app like a simple game.
Stroop Effect(from WIKIPEDIA in 2011.01.21)
In psychology, the Stroop effect is a demonstration of the reaction time of a task. When the name of a color (e.g., "blue," "green," or "red") is printed in a color not denoted by the name (e.g., the word "red" printed in blue ink instead of red ink), naming the color of the word takes longer and is more prone to errors than when the color of the ink matches the name of the color.

* The positions of the answer buttons (Red, Blue, Green) change randomly each time.

Please see the following site for how to use this app.
https://android.brain-workout.org/stroopeffect/