Just Brush for the iPhone provides a very simple and easy way to insure that you brush your teeth for the dentist recommended two minutes. When you click on the blue circle, it starts the countdown timer. As the time decreases, the blue circle turns green.
When done, the blue circle is completely green, the timer reads 0:00, and a chime will sound to notify you that you have brushed for two minutes.
Use the calendar to check the dates when you used the app.