With this application, you can find out by phone number of the cellular operator (MTS, MegaFon, Beeline, Tele2, Yota, etc.) and its region. Always current information , because The application receives data from the online database. - determine the number from the call history - identify the number from the contact list For the application to work, you need an internet connection. MNP (mobile number portability) - switching from one operator to another while maintaining the telephone number