Here's a summer warning, if you head for pavement cafes or sit outside the bar.
It depends on the fact that so many people nowadays put their smartphones on the table in front of them.
Beware of scamsters who sidle up and offer you something, like greetings cards for sale, jewellery or even flyers.
The item is put on top of the phone, so you can't see it being snaffled - and, because of the distraction, you don't notice it's gone, for a while.
Here's an instance in London, where the police had made some arrests.