Fingerprint scan possible in ODK?

What is the general goal of the feature?
to use fingerprint within ODK.

What are some example use cases for this feature?

What can you contribute to making this feature a reality?

It's not, but if you search for fingerprint, you'll see that it comes up a lot. For this to be considered, it has to be filed at and the use-cases flushed out. One good first step is for you to file that request and link to the various threads over the years...