53% of violent thefts in Paris m and transit métro and transit thefts involve smart phones, including the ubiquitous iPhone. City officials even call it the "iPhone effect."
This is easy to understand. My wife lost her iPhone on the Muni bus here in San Francisco. The thief scoped the riders near the door and as the bus doors opened, he grabbed the phone and ran out the door. The doors closed and she barely knew what happened. I could see this easily happening in Paris. On the other hand, your odds aren't so bad. If you're standing at rush hour, you're usually surrounded by ten other people staring at their little screens. Still, a word to the wise...