According to the information the developer Walking Cat, the code of the new version of the operating Windows Phone , named GDR2 offers the user the ability to block calls and messages from certain numbers, or even block all calls and messages from those numbers that are not in the phonebook.
Devices that have this version of Microsoft's operating the HTC 8X and Nokia Lumia 1020 , but not open this feature, because it is not incorporated in the interface. Therefore, it will soon appear and similar applications that can take advantage of this feature and to offer the end user. Finally, they will stop the calls with annoying advertising packages for telecommunications and offers!