There are lots of options, I've got one of these Netatmo ones which was cheap and, most importantly, really easy to fit with a variety of different installation options.
Doesn't do the learning stuff but being able to switch your heating off remotely has been invaluable at times.
I have a netatmo too - the only 'smart' aspect is the heating comes on before the setpoint or something like that. Not that I am too bothered about that right now
I've turned that off as my heating struggles to actually hit the setpoint so it turned it on really early. It also lets you pull out graphs and data and shit and link in to Alexa, etc.
There are lots of options, I've got one of these Netatmo ones which was cheap and, most importantly, really easy to fit with a variety of different installation options.
Doesn't do the learning stuff but being able to switch your heating off remotely has been invaluable at times.