The first screen shows the list of weather stations. The ones listed at the top in red have summary data for weekly, monthly and yearly data for the sensor. All stations will report the current data for the sensor. If the list has changed, then the locations will be in yellow instead of red for a short period of use.
The app minimizes the use of internet connections by storing the sensor location list in a private file on the device. Reading from the local list (not requiring larger internet connections) is indicated by the red color of the location.