launchMode

LaunchMode is an attribute in Android development that determines how an activity is launched and how its instance is managed within tasks. It is declared in the AndroidManifest.xml on an activity element using android:launchMode. The choice of launchMode affects whether new instances are created, how intents are delivered, and how the activity participates in the task back stack.

The standard mode is the default. It creates a new instance of the activity whenever it is launched, allowing multiple copies to exist in the system and in different tasks as needed. singleTop is used when the activity is already at the top of the current task; in this case, no new instance is created, and the existing one receives the new intent via onNewIntent instead of creating a new object. If the activity is not at the top, a new instance is created as usual.

singleTask ensures that only one instance of the activity exists in the system. If an instance already exists in any task, that task is brought to the foreground and the existing instance becomes the root of its task; onNewIntent is called for the new launch. This mode is intended for activities that should manage a separate task and should not be duplicated.

singleInstance places the activity in its own dedicated task, which contains only that activity. No other activities from the same application share the task. This mode is rarely needed and is typically used for components that must run in isolation.

LaunchMode interacts with features such as taskAffinity and back-stack handling, and it influences how deep links and launcher launches are resolved. Developers should choose the mode based on desired task structure and instance management.