# App-to-app registration and authentication with the MobileID App
App-to-app registration and authentication allow the customer to offer registration and authentication capabilities for a mobile app through the MobileID App.
In the app-to-app scenario, the operations are started through the customer's mobile app.
# App-to-app operations process
The lists provide step-by-step instructions and detailed descriptions of the different operations. The sections in the lists correspond to the numbered steps in the sequence diagrams.
Registration, or device activation, is the prerequisite for authentication. This means that an end-user who has completed the registration process can authenticate their identity.