The Nest has two controls, a dial and centre button, and all is set with the two controls, unless you press centre button the dial is as default room temperature.
The smart bit is it can learn, so if you turn it to 20°C at 6 pm every day, it assumes you want 20°C at 6 pm every day and it slowly builds up a pattern reading both what you repeatedly do, and how long it takes to heat the room, and the wifi weather report. So once you have used it for a month or two it auto changes the temperature using your input altering the dial, it is really smart, and I never bother changing temperature when I leave the house, as smart with that too, if both mine and wife's phones are not at home it auto turns temperature down, then back up before we get home, if you need to get your phone out and alter temperature some thing is wrong. It also has an occupancy detection so if there is a visitor in the house it will not turn the heating down because you have gone out.
So you use it like a normal thermostat, and it learns what you want. You can set a schedule if you want manually, but as default it does everything automatic. And if the boiler is opentherm then it alters boiler output rather than simple on/off, although mine is not opentherm and it still works well switching boiler on/off. I have Nest Gen 3 as it also controls my hot water, but think the central heating bit is same as Nest e.
There are two draw backs, it no longer connects to TRV heads, support for Energenie TRV heads was withdrawn, and they will not work in Master/Slave mode, however think only EPH thermostats do that. However I have found setting the program on the TRV heads to match the program on the Nest works well, so using £15 TRV heads not £40 TRV heads, but as to if this will work for you depends on design of house.
Hive does not have the same cleaver algorithms to Nest, it is no where near as cleaver, but it does have dedicated TRV heads that send a signal to the wall thermostat, however since the dedicated TRV heads are more expensive at around £50 each, for a whole system Hive is more expensive than Nest. EPH like Nest does not link to TRV heads, and as you look at the range of "Smart" thermostats no one thermostat does it all, they all have plus and minus points.
As to geofencing due to lock down not really tested, but when we did do a long trip I checked room temperature with the Energenie TRV heads so not accessing the Nest software and it had reduced temperature. I can it seems set the TRV heads to geofence but have never bothered.