Hi @mguze! I know plenty of people would like to use fingerprint readers, but don't know of any such integrations with ODK Collect. I'd encourage your developers to join this topic and describe what the SDK enables. We could then suggest ways of how best to integrate it with ODK Collect.
Oh, and when you get a chance, please introduce yourself here. I'd also encourage you to add a real picture as your avatar because it helps build community!