9º Dígito Leucotron is a free Android app developed by Leucotron Telecom, which automates the insertion of the ninth digit to mobile numbers in Brazil according to the schedule of Anatel. The app is designed to make it easier for users to update their mobile contacts with the ninth digit, which is now mandatory in Brazil.

The app is designed to work with contacts stored in the phone's internal memory. If your contacts are stored in SIMCARD, you will need to use the resources of your schedule to copy them to the device's internal memory. It is also important to note that synchronization with remote accounts like Google, Yahoo, and Samsung can manipulate the contact list. If after inserting the ninth digit, the number returns to the original format "alone," check the timing with these accounts. The Samsung account, for example, usually bounces back into shape after one day.

The ninth digit is already present in the mobile phones of several states in Brazil, including São Paulo, Rio de Janeiro, Minas Gerais, and Bahia. On, the ninth digit will be added to the mobile phones of Paraná, Santa Catarina, and Rio Grande do Sul.