Can I set usage time for selected apps?

You can select a time limit for using applications each day when a particular profile is activated. For example only 20 minutes of Facebook during working time or at school.

How to set it up?
1) Create a new profile
2) As your first blocking condition, select time and specify your working time- or other time you want to limit your device usage
3) At the top right corner press "Add +" and select usage limit- select how you can use the apps for. 
4) Continue the profile setup by selecting the blocked apps and a profile name before pressing create and activating it.