It is important to verify that your phone’s location settings are configured correctly when using the tado° App on an iPhone. These settings are essential if you want to use Geofencing on tado°. In order to check them open the smartphone settings and look for the Location submenu, found in the Privacy menu. Here two settings are very important:
Location services have to be turned on.
tado° has to be one of the apps that always gets location updates.