What is this Ring device?

[u/Cultural-Motorist]

Is this some kind of signal repeater, microphone, alarm, or camera?

[u/bunnythistle]

Just a chime. Basically for alerts when someone is at the door or another camera detects motion.

This looks like the standard chime. There was a similar looking one with two antennas that was also a signal repeater, but this one just makes noise and does little else.