Wow. Let me say that again but with added exclamation marks: wow!!!

Google has officially released a Google Earth client for iPhone and iTouch users. It's available right now from the iTunes App Store, and best of it is free.

Actually, scrap that, because the real best of all bit about the iPhone Google earth client is just how jaw-droppingly stunning it is. Most paid for apps on the iPhone leave you with a little taste of disappointment mixed with resentment in a kind of 'I paid how for what now' sort of a way.

Google Earth for iPhone is the kind of application that is worth money, real money, a decent wedge of real money in fact. Yet it is free. You know, it makes me kind of want to give Google a hug again after having been kicking it in the Googlies for so much of the time recently.

According to Google Earth product manager Peter Birch "Since we launched Google Earth for the desktop in 2005, we've had over 400 million unique downloads" and now with the free download "you can fly through the same 3D immersive world of Google Earth you've come to love, without having to fire up your desktop computer."

There really are so many reasons why he is right on this one, from the touch interface just marrying up with the Google Earth interface so perfectly, to using the auto-tilt function to move the horizon into view as you lift the iPhone up for example.

The ability to fly from one side of the world to the other with a swipe of your finger is incredible, and all in your pocket as well. Of course, one touch brings you a view of wherever you happen to be thanks to the My Location functionality. Not forgetting to throw in the eight million or so Panoramio-geo-located photos of places to view as well.

For me, I just love the ability to search for places, businesses, and landmarks using Google Earth to return full details of businesses including reviews, photos and user content. Couple this to the "search near me" feature and it is just so cool.

OK, so don't expect absolute desktop-like performance on your iPhone, but you might be surprised as to just how close it gets. Around 10 frames per second is good enough, to be honest! Oh, and if you don;t have a connection at any point, no worries - there is an offline mode which lets you work from your existing cache!

If the iPhone needed a killer app, then this might just be it. It really is so much more refreshing than a virtual pint of beer. Oh, and it is great for partying in other folks pools as well...