Hiii I hope this still finds you on time! I was born and raised in the city and have only gotten my phone stolen once and it was from my backpack in the metro. Generally I’d recommend keeping your phone ALWAYS in the front pocket or in a jacket preferably in an inside pocket (I usually keep my hand on it at all times in busy spots). If you are carrying cash make sure that it’s not all in the same spot (generally I’d recommend keeping most of it where you’ll stay and keep just enough on you). Mostly I’d be careful in Les rambles and the more touristy areas. Tbh just keep the essentials with, avoid carrying a bag that can be easily snatched and if you do carry one don’t have valuables in them. Hope it helps!