With a Tiimo subscription you can have have up to 5 different profiles. You make a profile when signing up, but to create another one you simply go to the Me tab in the app, and choose Add new profile (Currently only on iOS).
If on Android you will need to log in on the online calendar. When you're logged in, you can see a bright green box with an initial of the calendar's user name. Press this green box and you'll be able to add a new profile and shift between the calendars as well.
You shift between calendars on smartphone or tablet by logging into Tiimo app and go to Me and then switch profile.