Viber is the best application for your phone and is the main analog of the famous Skype program. It allows you to connect with friends and other users of the program. The app has many functions, including sending text, photos, and video and making free calls. These features can be used with your mobile number. Your mobile number will serve as the main identifier of the system. After activating, sync is done with a list of possible telephone contacts. This allows you to identify all users and add them to the system.