Do you tell yourself "I just want to watch videos for 20 minutes and go back to work"?
This application Alerts you when you have used a specified amount of time on a list of apps you choose.
On opening the app, giving it the required permissions, and choosing the apps you want to be notified of your use, you get notifications after 20 minutes of consistent use. You can change the time on the app as required.
The app automatically selects popular social media apps on opening.