We have developed an Android app that tracks vehicle journeys, where each vehicle has a BLE device installed that wakes up when the vehicle is started.
To identify when the user is in the vehicle and when we should start tracking their journey, the Android app implements a foreground service that runs a BLE scan (via Android's BluetoothLeScanner) to look for the BLE device. On finding the device (after it wakes up) the scan is stopped and the app will connect to it and retain its connection until the journey ends.
This works well on most Android devices however we are seeing an intermittent issue where the BLE scanner doesn't find the BLE device for minutes after it wakes up. Sometime as much as 5 minutes.
The BLE scanner is configured as follows:
- Scan Mode = Low Latency
- Match Mode = Sticky
- Callback Type = All Matches
- Report Delay = not set
- Scan Filter = a device address is set to look for a specific address
We have also implemented a wake lock to ensure the scanning process continues even when the app isn't in the foreground.
We have experienced the delay on some Android 10 devices.
The app targets Android 10.
Any help would be greatly appreciated.
Cheers, Andy