I just bought an opensprinkler pi. I have a pi 3 sitting around that I got free. I’m looking forward to setting all this up this weekend.
Just a FYI it seems as though TIAO is “currently working on the next generation of the TIAO smart sprinkler controller” from here:
https://www.diygadget.com/tiao-smart-sprinkler-pi-16-station-sprinkler-controller-open-source-desktop-mobile-app
So they must be still selling the clones enough to make it worth while to put development time into it.
I bought the O.S. hardware because O.S. is running the cloud servers and it’s a way of kicking some money to support that, even though I will mostly not be using the cloud server (since I have a permanent VPN to the remote site the sprinklers are at)