There is no APIs provided till now for fingerprint scan in RhoMobile.
But you can always create a native extension and achieve the same.
can you provide a sample or an example on how to create a native extension and call it from rhomobile?
I haven't worked with the fingerprint API, but I did a quick search, and the Local Authentication API is pretty simple, since all it allows an app to do is to ask for the user to validate and it will send a notification with a yay or nay.
Other than this and some keychain support, there is no other access provided to the fingerprint scanner. For example, it is NOT possible for an app to read a fingerprint and store it. It can only be used to validate that the user who registered the fingerprint(s) has responded to a request to authenticate.
Here's a good overview:
You send a string that is displayed along with the prompt, you get a notification of pass/fail/cancel.
I've written a couple of Rhodes native extensions that send callbacks - one for virtual keyboard events, (show/hide/etc.) and another for mDNS/Bonjour discovery. Looks like Local Authentication would be a snap!