Adding an account is always initiated from the server. By scanning an enrol QR code or clicking on an enrol deep link, the Mobile SDK will start the flow to add an account.
An account can be removed from the app as follows:
Accounts can also be removed through the API of the server. However, for this to work push messages, and preferably a direct call to the Message Center, have to be implemented.
When the last account that requires a second factor, is removed, the user's PIN and biometrics will also be removed. This effectively resets the Mobile SDK.