When user presses back, the task is cancelled without warning and stays in state "Started" so the user does not know what happened and might have unintentionally pressed back to go back a step.
This is why we have to disable the back-ability of the tasks. Leaving the task can be done with the 'X' button and going back a step is not an option for most tasks.
We can show a Toast when user presses back that says "Cannot go back in steps in this task. To exit task and discard results press X"
When user presses back, the task is cancelled without warning and stays in state "Started" so the user does not know what happened and might have unintentionally pressed back to go back a step.
This is why we have to disable the back-ability of the tasks. Leaving the task can be done with the 'X' button and going back a step is not an option for most tasks.
We can show a Toast when user presses back that says "Cannot go back in steps in this task. To exit task and discard results press X"