Why are you asking in server forum?
Anyway, the app should be running in the background if you turn off the screen, but some manufacturers customize firmware on their phones to "save" battery life. Maybe that's the case on your phone as well. I guess the only way to know is to check system logs.
Hello
Few minutes after the screen of my smartphone switch off, traccar client stop sending data.
Is there a way to have client still working ?
Using Huawei P8
Android 5.0.1
Thanks for your help !