It is possible to add tags to users. Just click on the menu "Colleagues", then on the card of the colleague who you would like to tag. All you have to do is to select the tag or tags you wish to assign to him or her. There is no limit on the number of tags you can add to a user.
You can tag your users by function (electromechanic, boilermaker, etc.) or by team (night shift, weekend team, etc.).