The Text box doesn't show Bluetooth status correct

[Taifun]

it does not make sense to use a timer to check the connection... once the isConnected property returns true, it will stay true, see also

Change Text when Bluetooth disconnected

according to the documentation Connectivity DisconnectOnError Specifies whether BluetoothClient/BluetoothServer should be disconnected automatically when an error occurs. I don't think so, because you forgot to poll the bluetooth device as @ABG suggested as the bluetooth protocol was designed, there is no way to detect, if a connection still is alive, therefore you have to send regularly (i.e. poll) some data to the device. And if you get an error, then you know, that the connection was…

Taifun