What is the purpose of the add-on application My Navigo Tickets?
On NFC Android smartphones (without secure element), your transport tickets and passes are securely loaded into the add-on application My Navigo Tickets (except for Samsung Galaxy models, see §8.2).
You must not delete or uninstall the My Navigo Tickets application, as you will lose the tickets stored into it.
The only way to ensure that you won’t lose your tickets is to update the application, either from the Play Store or from the Settings > Apps menu on your mobile.