Enable the local DnD feature (touch the officeXtend logo in upper left corner)
Local DnD will allow the app to remain registered but will prevent calls from being presented to the application. This is the preferred method rather than logging out.
Note: Local DnD will not set any associated physical phone on DnD.
Touch "Reset" (Android) or "Log out" (iOS) in Settings
This method will also reset call history and other local items each time you logout.
On the desktop client, right-click on the officeXtend icon in the dock or system tray and choose Quit. This will exit the application and you will no longer receive calls. When you restart the application, you will be logged back into your account.