Thirdlane Mobile Dialer is a Dialer - not a softphone, it uses Thirdlane PBX or Thirdlane Multi Tenant PBX to call back your phone and connect you with the party you are calling - simple and reliable. Key features of Thirdlane Mobile Dialer. PBX Caller ID. Person you are calling sees your PBX Caller ID - not your mobile phone number. Call Forwarding.