@Dancaw 

You need Kasa KH100 hub which is sold as a kit with one TRV. There are some user reports that Tapo H100 hub is also compatible, but these have different firmware and you may encounter problems.

Tapo app is compatible and will pick up KH100 hub with TRV's once configured in Kasa app. Currently I observe there's a feature parity while the UI of Tapo is more compact and easier to use.

For boiler automation you need external service like Home Assistant to integrate products of different vendors, and of course proper hardware to control the boiler. Check my other posts/threads for more details. In some cases it would be better to replace current thermostat with simple NO/COM switch and set up the schedule and automation only in HA based on TRV heating demand. I saw many ridiculous ideas to control the thermostat (and boiler connected to it) by its target temperature, instead of just telling the boiler to turn on or off.