If you cannot make a connection between the Apple Watch app and the iPhone, two things are important:

  • The iPhone and Apple Watch cannot connect if you are using beta version of iOS. 
  • Sometimes you cannot make a connection between the ThermoSmart app on the iPhone and the ThermoSmart on the Apple Watch. The solution is to log out and in again to the ThermoSmart app on the iPhone. 

You can then establish a connection the the Watch.