Using a little Arduino programming the fingerprint reader checks to see if you have access and if approved the Arduino Mega development board unlocks the door using a micro servomotor.

Eufy Smart Lock C220 — $110 $150 27% off Eufy. The Eufy Smart Lock C220 may be controlled from anywhere using the Eufy Security app, which provides access management, real-time notifications ...

Well good news — there’s a new smart lock in the works that does away with all these cumbersome key- and phone-based unlocking schemes. Instead, the Ola lock uses a fingerprint sensor.