I emailed support earlier and got a very quick response but wanted to add it here as well to see if others would add traction and visibility.
When adding the Rachio to a WiFi network, the Android app requires the SSID to be broadcast. You cannot add the Rachio to a WiFi network with a hidden SSID. As a suggestion, the Android app should support hidden WiFi networks or WiFi networks that do not broadcast their SSID. There should be an option to manually type the SSID. The end user should not be forced to change their network configuration to add the Rachio to their WiFi.