A free program for Android, by Tomu.

The Procrastination Timer app will help you to keep track of the amount of time that you spend studying and the amount of time that you spend procrastinating. It is useful for those students who have to study for finals. With this app, you will know how much time you have left for studying, so you can avoid procrastinating too much. You can also use it to keep yourself from being too lazy.

The application is based on the idea that we all have a natural desire to be productive. However, when we are not working on a task, we tend to be lazy. This leads to a lack of productivity and the completion of tasks that we have been putting off for a long time.