With one touch anywhere on the screen this timer starts. Touch again anywhere to stop the timer. That's it.

Don't worry about double clicks or mis-clicks. Once the timer is stopped it stays stopped until you press the reset button 5 times. I created this to time a race and was annoyed by double clicking other timer apps and losing my time.

It also stops the time if you shake the phone which is useful when racing and you need to stop it quickly and Android registers a click as a swipe or anything else weird.