Bluetooth client does not disconnect when bluetooth off

[Taifun]

generally see here concerning the IsConnected property

Bluetooth (classic Server and Client) IsConnected does not report disconnected state? Android 8

the IsConnected property never was able to detect, that a connection is gone see also Change Text when Bluetooth disconnected - #8 by Taifun 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 lost… see also A simple Bluetooth Chat with App Inventor 2 Taifun Trying to push the limits! Snippets, …

this thread might help

How to program an app that sends notification when bluetooth disconnects

Dear Maggie, I've just developed a couple of days ago, an app that behaves like a BT gateway between a smartphone and an Arduino, which is equipped with a HC06. In attachment you can find the .aia, the Arduino code (in txt format) and a document that explains all the HW and the SW (at least in my thought ). It operates on the basis of a watchdog (more or less). In few words: the Arduino board sends an "alive" character to the app every two seconds. If the app does not receive the "ali…

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