Our Android application connects to our nRF52 (BLE) within 2..3 seconds while the APP in foreground. The Advertisement is picked during a periodic scan performed by a dedicated service.
When the APP is in background, although the scan is performed (proved by breakpoint, and an incrementing counter), there are no scan results.
As soon as the APP is bough into foreground, the scan picks the device normally.
Both the Android API StartScan() and the deprecated StartLeScan() have exactly the same behaviour.
What is required to make the scan work in the background ?