I can't say I have been in exactly the same GPS scenario as the OP, but I did let my ex-gf use my phone once cause her sim plan got disconnected since she had not updated her card details on her carrier.

She takes my phone, and calls support and is on speaker. I didn't think too much, cause I don't punt when I'm with someone. But I still had tapatalk installed cause I do like reading the shit stories people post here and out of nowhere I get a notification on tapatalk and my screen turns on and I can see the notification icon on the locks screen.

Good thing that I have "hide sensitive notifications" turned on for the lock screen and I believe my ex had locked the screen when she put it on speaker.

Had to make up an excuse that I had to scan a bar on myfitnesspal and took the phone from her and deleted my wechat and tapatalk for the time being lol

Sometimes I feel like I should get a spare phone just for this.