@Wayne-TP , yes I am interested on  a dry relay for sure (should not swich signicant power, the best would be if it could work from battery), the mising of that is the largest disatvantage of Tapo smart device portfolio - I should use Shelly and Tapo parallel because of that gap.  Gate, garage opener are some examples but even if it can swithc small power only it can controll another relay from a thirparty and evrything from that point..)

  @BGabor This is exactly what the S210 is... 

I have several operating pumps, fans, lights, diesel heaters. Some on a boat at 12v, some 240v in a house. Once you get over the fact that they look like a house switch, you realise they are just a wifi battery operated multi function relay.

  @Charliepsycho  thanks for your prompt answer, I was considering to use Tapo switches as a Multifunctional relay, but they have a giant size. I could use S210 as input switch as well, but two connectors are missing here as well I think. ( to link this "relay" to the already wired push buttons)..

I disassembled few Tapo devices as in general they have all needed functions already - just few connectors or just a new boxing would be needed - but I was not brave enough to make some soldering. Like you told S210 a multi-functional relay, 200B is an input switch etc - so minimal and marginal modification would be needed to add them to their portfolio.

To be honest I had no closer look on Tapo S210 until now - just was thinking in general to use it as smart relay  - , but I will have a closer look now to double-check the size of the core electric parts of S210 and make a try to use it without the buttons what is the root cause of the size I hope..

Thanks

Gabor

  @Charliepsycho sorry, you asnwered all three items I think, I would like to give you a more comprehensive answer from my point of view.

Why S210 does not a replacement for
1) Shelly PLUS i4  - because of missing connectors and size
2) Shelly 1 Mini Gen3 - because of size (and it could be AC230V operated as well, but it is not an issue..)
3) Woolley SA-018 Smart Switch - I don't want to change the appearance of my switches in my house - just would like to build something behind my switches..

Thanks, I hope I was more clear now..

Gabor

  @BGabor Yes, those shelly switches look nice, but they only switch 240v. The thing about the Tapo switches is that they are true isolated relays, so they can switch any voltage you like. I agree the size can be an issue, but if they are going to be out of sight, then it doesn't matter (I have a few in the attic, it means I can still operate the switch manually if everything goes wrong!)

In terms of how they look, well that's a taste thing, I think I have a dozen different switch styles around my house, the tapo ones at least have a clean aesthetic!

I've been through a few different smart ecosystems (samsung smartthings, d-link, smartlife, tuya etc) and tapo seems to be the least flakey!

The main thing to me is the app infrastructure. TP-Link will hopefully be around a while, they seem to be making a cohesive app ecosystem (e.g. bringing Kasa appliances in as well) they also seem to be fixing bugs fairly regularly (although there still are bugs!) So I tend to bend the rules to stay in the tapo system.

  @Charliepsycho  "So I tend to bend the rules to stay in the tapo system." - me too.. :-)

Regarding " they only switch 240v" the Shelly I shared, has a Dry(isolated) and Wet contacts (switching 240V as well)

Thanks

Gabor