In some cases, during the process registration, cannot design through social networks like e-wallets, bank accounts, etc. In such cases, usually, in applications, for ease of use, developed a particular form for a phone number with a pre-selected country code and convenient number entry. But exist the case when users also should be able to sign up by e-mail. For such an example, we have designed the unique cellular number mask that appears when the user starts typing numbers.