Yes! To get you perfect voice quality and clarity, Sideline uses radio towers to transmit voice signals (same as your phone carrier) to make calls. For this purpose, we need you to register a phone number (cannot be a voIP number) as a mandatory part of the account creation process.
If you don’t have an active phone number, you may be interested in our other application, Textfree! Check it out here
If you recently got a new phone or changed your mobile number, simply login just as normal. All your account information will transfer over on its own!
If you experience any trouble with this, please do not hesitate to contact us-we'd be happy to help!