What is the difference between a foreground service and a regular service?

A foreground service runs "in the foreground" and is connected to the user interface, which requires displaying a persistent notification. This prevents the system from terminating the service due to lack of memory. A regular (background) service can be terminated by the system at any time to free resources. Foreground services are used for tasks that the user is explicitly aware of (e.g., playing music, location tracking), whereas regular services are for background operations without direct user interaction. To start a foreground service, use startForeground().

// Example of starting a foreground service
val notification: Notification = createForegroundNotification() // Create notification
startForeground(NOTIFICATION_ID, notification) // Start service in foreground

// Example of starting a regular service
startService(Intent(this, MyBackgroundService::class.java))

Key differences:

Characteristic	Foreground service	Regular service
Lifecycle	Less likely to be terminated by the system	Can be terminated by the system
User experience	Associated with visible activity, requires notification	Runs without visible UI
Launching	startForeground()	startService()
Use cases	Playing music, navigation	Data loading, synchronization