What is the difference between the singleTop and singleTask modes of launching activities in Android?

Launch modes for activities in Android determine how the system manages instances of Activity in the task stack.

• singleTop: If the Activity is already at the top of the stack, a new instance is not created, and the onNewIntent() method is called. If the Activity is not at the top, a new instance is created.

• singleTask: There can be only one instance of the Activity in the task stack. If such an Activity already exists somewhere in the stack, the system brings it to the top and calls onNewIntent(), destroying all Activities above it.

Example:

• With singleTop, if the user re-launches an Activity that is already on top, a new instance is not created.
• With singleTask, if the Activity already exists in the stack, the system returns to it, clearing the Activities above.

Thus, singleTask ensures the uniqueness of the Activity in the stack and prevents duplication, while singleTop optimizes behavior for re-launching if the Activity is already on top.