Latest version seems to help with Network busy error messages. Also can't get it to work with tablets in landscape mode. That said can't beat this device in the bang for the buck category as devices with similar ONVIF / POE functionality run a lot more than this unit.
Works great with galaxy s8. Doorbell connected via Ethernet for 2 weeks now and works fine. Only problem is if you switch between Wi-fi and 4G for around five minutes it says network busy but if you close program and restart it, it works again.