Earlier quoted context omitted.
Phone's should have a travel mode, where it backs up all your data to the cloud and wipes the phone clean.
Why does that need a special mode? Just back up your phone and factory reset it.
'[X] You are proposing a technical solution to a non-technical problem'
The border agent of ${COUNTRY} doesn't care if you wiped your phone accidentally or deliberately; his flowchart says 'access subject's chat history on phone'. If that's not possible, goto 'reject'.