Pebbledoro is a great example of this feeling. It is an extremely simple but very useful app. The app was created by developer mertdikmen, and is an app for implementing the pomodoro method.
Essentially the entire app can be seen in this screen shot:
If you are not familiar with the pomodoro method it involves a productivity system of working for 25 minutes and then breaking for 5 minutes, and then working for 25 minutes and then breaking for 5 minutes. It is a great system to help you increase focus. Orthodox pomodoro practitioners use a tomato timer, but pebbledoro replaces that with a simple app on you wrist.
As you can see in the screenshot there are just three controls: Start, stats, and stop. When you start the little black square will begin to appear at a rate of 1 per minute. When it is done you will feel a small buzz on you wrist. The break will not start immediately so you can finish up whatever you are doing that moment, and then push play again to start the break. During the break the black squares will disappear at a rate of 5 per minute.
The stats button will tell you how many pomodoro cycles you have completed using the app, which is not incredibly useful but might be fun to know.
The stop button will cancel the pomodoro.
You can still receive notifications on the watch while using this app, although that might throw off you focus.
Well that is about it. A simple but useful app for the Pebble or Pebble Steel.
Thanks for reading, and remember, live better.