I was asked a question recently that gave me pause for thought. "Should I buy a designed-for-the car GPS unit, or a GPS app (like the TomTom app) for an iPhone?"
I came to the conclusion that it depends on a number of factors, not least of which whether or not you own an iPhone to start with. Suppose you do - it makes sense not to splash the cash on another GPS device when you already own one. The TomTom app for iPhone is perfectly capable, albeit a little small on the screen. The real issue I suppose would come from those who insist on talking on their phones whilst driving, because no matter which way you look at it, having your phone be your turn-by-turn GPS is mutually exclusive to talking on it. Personally I don't think that's a bad thing. Also, it's one less device to carry around with you.
But what about the tried and true, built-for-the-purpose hardware? Well it's exactly that - built for the purpose. The GPS reception is undeniably more robust and the multichannel receivers are far better than those found in most phones. The screens are typically bigger and more responsive and they normally have removable flash cards for map upgrades. iPhones don't - you're stuck with the onboard memory which limits your choice of maps when it comes down to it.
So which should you buy? Honestly - if you have an iPhone, get the app and be done with it. It's $60. There's just no point in buying a proper GPS for an extra $70. However if you're one of the millions of us who aren't in the Apple camp yet, then a GPS is your best bet because it will work better, and be cheaper than shelling out for a phone, data plan and GPS app.