Some people use multiple thermostats in one household. For example, if you have separate heating groups for upstairs and downstairs, or if you have a home business with a separate arrangement.
Unfortunately, many people find it inconvenient to manage multiple ThermoSmarts. Each ThermoSmart has a separate log in and password for the portal and apps. To switch from one ThermoSmart to the other, you have to log out and then log in again.