You can tell your Flow is connected by checking the Bluetooth icon on the companion app's live screen. The Flow application displays three different possible Bluetooth states.
Flow is connected to the application, measurements are transferring in real time.
Flow is not connected to the application, you are not receiving real-time measurements, though they are being stored in Flow's internal memory and will download as soon as you connect to the app.
Your phone's Bluetooth is deactivated.
Understanding your Bluetooth connection
Flow communicates with its companion app through your phone's Bluetooth connection. There are key functions that need a connection in order to work.
Pollution levels are always being collected by Flow and will be transferred to the app when Flow is connected. This can take some time if your Flow has been tracking for a long time with no connection.
GPS data is NOT collected unless your Flow is connected by Bluetooth. When Flow is connected to the companion app, it sends data from the various sensors to be processed and then displayed in maps, graphs and other useful ways.