Standard : This launch mode generates a new instance of the activity in the task from which it originated. It is possible to create multiple instances of the same activity, which can be added to the same or different tasks.
SingleTop : This launch mode is similar to the Standard launch mode, except if there exists a previous instance of the activity on the top of the stack, then a new instance will not be created, but the intent will be sent to the existing instance of the activity.
SingleTask : This launch mode will always create a new task and push a new instance to the task as the root one.
SingleInstance : This launch mode is the same as the SingleTask launch mode but the system doesn’t launch any new activities in the same task. In a scenario where the new activity is launched, it is launched in a separate task.
