A few years ago, during one of the most entertaining job interviews I’ve ever had, one of the questions asked was, “how many computers do you have at home?”
Even at the time (circa 2005), this was a bit of a head-scratcher for me, and I had to ask what they considered a “computer,” whether it mattered if the computer was in active use or stored in the attic “just in case”, and if games consoles counted. The main purpose of the question, though, was to act as a nerd detector. If you even have to think about the answer, you’ve passed some kind of barrier.
The same is happening in mobile development now. If you are looking to hire a mobile (web) developer, ask them how many “mobile devices” they own. If their answer starts with “Wellll…”, then there’s a good chance you’ve got a live one on your hands.
(Warning: do not use this piece of advice after July 2012. I’m guessing that by that point, it’ll be much more common for techies to have multiple mobiles on hand. Right now, though, we’re at a point where it’s still mostly the hard-core who wander around with more than one.)