I understand that Ring is the leading contender on the smart doorbell market. but I also understand that it does not support Ring.
So is there any other reliable doorbells similar to Ring that are integrated with ST?
Short answer: no.
Longer answer: a lot of people use one anyway and like it. See:
Yes, reviewed that post as well as the 247 post on Ring.
It seems that there is really no perfect solution on the market yet.
The ZLink seems to be very good deal for the price, but I don’t see any reviews of it at all.