Hi. I set up my Rachio sprinkler controller today. Everything went smoothly enough. However, one thing I did not like about the setup process in the iOS app was that I could not paste my password into the app while creating an account. I use a password manager to generate all my passwords. On my iPhone, I will typically copy the password from the password manager app and then switch to the whatever app I'm logging into (or signing up) to paste the password. It seems I couldn't paste into the Rachio app. Just a suggestion!
PS: with iOS 11, you could add the ability to autofill a password from an existing account on the rachio.com website if the user has already signed up in a browser first and saved the password to iCloud Keychain. From what I've seen, it is a very easy enhancement to add to the app.