- Save 90% off call costs with “virtual landline” iPhone app Dublin based internet telephonics company Blueface have recently released an iPhone app, known as Banter, that claims to save customers up to 90% off mobile phone call costs. Upon downloading the free app and creating an account, the user is given a “virtual landline” number based on their location. With this new virtual number users can then make and receive calls at a reduced rate when compared to normal and more expensive mobile phone call costs.