Before you leave
Share the route with someone you trust: where you are sleeping, which transfer you are taking, and when you expect to arrive. It does not need to be minute by minute. A message when you set out and another when you settle in is enough. Keep copies of your documents off the phone, in an email to yourself or on paper.
Check how to call a taxi or a ride you can track, and write the address of your stay in the local language. If the phone dies, that note gets you out of a problem. Caution does not drain the trip. It lets you pay attention to the place.