I unfortunately had to replace my Garmin Edge 530. Parallely with the new device came the latest Firmware- and iPhone App-Updates (Firmware 9.75, App 5.7.3). When i then tried to setup the new Edge 530, it stalls more or less directly after being connected to the Connect App via Bluetooth. The device is unusable because it doesn't last even a minute before it restarts again.
Using my old device (still working, only broken back) it shows the same effect and is also unusable.
I tried to connect and disconnect the new edge 530, setback to default, setup with and without al least 20 times today, deleted both devices from the app, deleted the Bluetooth connections also 20 times. No effort. The setup without bluetooth connection works, but as soon as the device is connected to the iPhone via Bluetooth it begins restarting. A very frustrating process.
No other Bluetooth issue with the iPhone actually.