Hope that someone can help, we have an app that works well on smart devices on versions of Android prior to 8.0. We have A5s, A6s and J6s all displaying this issue.
Background: The app on the smart devices connects to a handheld barcode scanner, the scanner scans 2D barcodes and the app reads the barcode and responds by making the scanner beep and flash a sequence of long and short beeps and different coloured flashes. The user doesn't need to interact with the smart device as the scanner response is adequate for most of the scans.
Issue: Despite the user scanning barcodes the scanner stops responding after about 10 minutes. The bluetooth message to the smart device is still active, the screen displays the resulting scan, but the response from the smart device to the scanner stops. Then after a indeterminate amount of time, all the responses will be delivered to the scanner. When testing different devices the delay is approx 10 minutes, and the A5, A6 and J7 will all stop at the same time. It does look like a setting within Android that is powering down the outbound bluetooth signal. This only occurs on on Adroid 8.0 or above.
We have tried multiple options. Cleared the cache. Turned off power saving mode. And managed to get into the Optimise Battery Usgage and turned off optimisation to all apps. And the issue continues. The fact that the outbound bluetooth goes to sleep after 10 minutes despite us using twoway bluetooth comms, does seem to be a bug. But any advice would be appreciated.