Honestly it does seem like a hard app to make but the button is delayed. If you google reaction time benchmark, it shows you your reaction time accurately. I really wish this app was better because Im not always around a computer. Another thing is maybe if they changed it to where you held down the button and let go instead of taking the time moving your finger towards the screen or accidentally tapping "stop" while getting as close as possible. I know it Doesnt seem much of a difference but my true average reaction time is .190 ms. And on this app with the delay and having to press the button its around .3 ms. Hopefully the developers can see this and give it a try. Just where you have to hold the button till the screen changes or something. Im going keep the app and see where it goes. But other than that keep up the good work.