Are you more than 2 hours non-stop at the computer? More than 2 hours reading? Stop, take a break and rest your eyes.
This app, available for smartphone & watch (Wear OS) is very simple. Start the 2 hour interval and the app will notify you every 2 hours, good time to take a break.
*Important, for a correct operation, please don't kill the app. Once it is working, cover the watch with your palm or if you have a press button, to leave the application working in background.