I this previous posting, I wrote about how tapping an NFC Tag, with the “NFC Tasks” app installed, can cause a phone to perform an automated sequence of actions. I have learned that in order for this to work, any lock screen on the phone must have been unlocked, and that the phone must not be asleep.
I find that sensible.
And there do exist rooted users, who will go through complicated measures to bypass this. But since my phone is not even rooted, this subject does not apply to me.