One thing I like to do is watch the sunset. Usually when I am outside I try to find a place where I can watch the sunset. Since the time of the sunset varies day by day I sometimes have to check beforehand what time a sunset will be. Also sometimes while outside I lose track of time. This android app solves these problems. It calculates when a sunset will be, and it will provide aural notifications as the sunset nears.

The notifications (and/or beeps) will begin 20 minutes before the event. The first 18 minutes will be one beep a minute. The next 90 seconds will be a beep every 10 seconds. Then the last 30 seconds will be a beep every 5 seconds. The last 15 seconds will have longer beeps.