I am making an application for work that has many user devices, and only a few administrator devices.
The application uses fingerprint authentication (and has a feature for pin entry if your finger is cut or otherwise somehow unrecognized). The application is for emergencies, so I need to be able to have administrators be able to authenticate themselves on user devices.
Is there a way to copy an administrator's fingerprint from his/her device and add that to a user's device? In the case of an emergency, the admin may not have their device, but only have access to a user's device.
If you're using Android 6.0 fingerprint APIs, I'm afraid to tell you that technically is not possible. For security reasons, the fingerprint remains safely encrypted in the device, thus it's not possible to extract it.
A Google engineer, part of the team responsible for the Nexus 5X and Nexus 6P, replied the following, to an user in Reddit:
Accordingly, it's not possible to duplicate fingerprints that you cannot extract from your application.