For admins
Extensions
An extension is a number that rings a phone: for a person, or a shared one like a reception desk.

Adding one
+ Add, then:
- Quick add: just a name. It gets the next free number.
- Guide me: number, name, person and a phone, step by step.
Belongs to a person? Choose who, or Nobody for a shared phone.
Phones on an extension
An extension can ring a desk phone or a phone app as well as the browser. Open it and choose + Add a desk phone or phone app. See Desk phones and phone apps.
Removing one
Open it, Danger zone → Remove extension. Its phones stop working and its number becomes free.
How numbers look
The number of digits and the ranges (people, shared phones) were chosen in the setup wizard. To change them, run the wizard again from System → Settings.