I don’t know where you’re located but I would look into any rebates from your water district, my Rachio controller was essentially free. It maybe cheaper and an easier setup.
Is nobody looking at Hunter Hydrawise irrigation integration?
I agree with sgnihttrams that it is a great sprinkler controller. The company was taken over by Hunter, so a lot of momentum behind them! I have a 12 station unit with flow meter and use two valves for doing partial water replacements of my fish tanks. Simple pipe through the wall into my two large tanks with carbon filters. Overflow water go to garden beds as well. Most of stations are used for the lawn sprinklers using MP rotator heads, but I also have one connected to a dropping system, two for micro jet irrigation and one for vegetables garden.
I’m not sure what functionality is available through the Hydrawise API but I could force some manual watering if very hot. My Netatmo is connected through Weather Underground and ST, so a lot of information. If anyone wants to start on a smart app, I am a willing tester!