In article ,
newshound wrote:

On my android phone, by default the USB port will only accept power. You
have to pull up a window and positively enable data transfer.

https://krebsonsecurity.com/2011/08/beware-of-juice-jacking/
3One attendee claimed his phone had USB transfer off and he would be
fine. *When he plugged in, it instantly went into USB transfer mode,2
Markus recalls.* 3He then sheepishly said,* ‘Guess that setting
doesn1t work.'2

OK so that's what the article said. I wonder what sort of cleverness it
is doing if the phone *really did* have the transfer turned off. Was it
perhaps exploiting a bluetooth or wifi vulnerability?

it likely used a usb exploit to re-enable it.

accessing data on android devices is relatively easy. for ios devices,
it's basically impossible.