You can change the name that appears for phone lines from the default [Extension] - [User] to something more meaningful. For example, if a user shares a line with your Support Department, you can change the line name to something like Support Line. Or if you want to separate work lines from personal lines in a place, you can make that distinction. After you make the change in Cisco Spark Control Hub for a user or a place, the new line name shows up on the impacted phones.
All devices for that user or place are updated.