Timer forgets time
User needs to set countdown time every time the timer is used. That means you cant use the timer for timing any repetitive task. Youll spend more time setting up the timer than you will spend using the timer. Also the timer "reset" function resets to zero (the end time) instead of the last start, countdown time. Start/stop taps must be on the text and not the black background which is the source of the comments about nonresponsiveness.
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Easy Stop Watch&Timer