I switched from Ring and Nest to the EZVIZ DB1 smart doorbell, because I wanted to eliminate a cloud dependency from the basic camera/doorbell functionality in my house. This doorbell has come up in these forums several times. I solved the button press issue by creating a smart doorbell push sensor using a Shelly Uni. I also did a fairly comprehensive review of the available compatible apps, plus a pretty thorough traffic audit, and I dissected the firmware a bit.
I finally have a smart doorbell that works both as an IP camera and a doorbell, with local HA integration, and reliable low-latency two-way phone comms. It’s not a perfect product, but when fully configured and combined with HA and Frigate, I think it is the best solution available right now.
I took detailed notes while I got everything working, and have written it all up in a detailed report. It’s a little long, but you can skip to the bit that interests you. Hopefully this guide will contain something useful for anyone currently using the doorbell, and anyone considering buying one.