iPhone & iPad app to experience the Stroop Effect



“StroopEffect2” is an iPhone&iPad app to experience the Stroop Effect.
It works on iPad and iPhone with iOS 9.3 or later.
Please see here for the Android version.
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.

“StroopEffect2” How to use


Tap the “Start” button on the startup screen.

The displayed “red”, “green”, and “blue” text is localized by language as follows:

English : Red Green Blue
French : Rouge Vert Bleu
German : Rot Grün Blau
Spanish : Rojo Verde Azul
Chinese, Simplified : 红 绿 蓝
Chinese, Traditional : 紅 綠 藍
Hindi : लाल हरा नीला
Tamil : சிவப்பு பச்சை நீலம்
Japanese : 赤 緑 青

The elapsed time [seconds] is displayed in yellow.


Enter the color of the text by tapping the “red”, “green”, and “blue” buttons in the center.

The positions of the “red”, “green”, and “blue” buttons move randomly every time.

There are 10 questions. The total time of 10 questions is recorded as the score time.

If it is incorrect, it ends there. Click the “Done” button to return to the startup screen.


To reset, tap the “x” button at the bottom left.


Tap the “Score” button at the bottom right to display a list of scores.

The first line of the score is the number of correct answers and the score time [sec]. Scores with “**” at the beginning indicate that the Stroop effect is off.

The second line of the score is the elapsed time [sec] for each question.

The third line of the score is the end time.

Swipe left to delete a score.

Email the score CSV file

Tap the “email” button to open the screen to send an email with the score CSV file attached.

The attached CSV file will have the following contents.

The StroopEffectSW column shows the Stroop effect ON/OFF.

“StroopEffect2” App Store

App Store

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