One of the first TED Talks I ever watched was a fellow from Microsoft demoing a new technology called Photosynth. It used hundreds of photos from Flickr, all snapped from different perspectives, to synthesize beautiful 3D models of popular tourist destinations—I think they showed Chartres during that demonstration—and it blew my mind, though it seemed decidedly like one of those tools that was too cool to ever actually see the light of day. Well, good on them, Microsoft eventually unleashed Photosynth to the masses, and now they've made an iPhone app for it. And it's terrific.

What is it?

Photosynth, free, iPhone. Basically, Photosynth is a panorama photography app. It's got Microsoft's Photosynth engine under the hood, stitching together as many shots of a given area—up, down, left, and right—as you feel like snapping to create a surprisingly smooth model of the space. Microsoft encourages you to add your panoramas to Bing Maps (if they're places of public interest, like a museum), or you can share via Facebook or Photosynth.net.

Who's it good for?

Pretty much anyone who likes to take pictures of stuff with their phone will enjoy this. It is very fun. And people who want to do their part to help Bing Maps usurp the online maps crown from Google.

Why's it better than alternatives?

There are a handful of solid panorama apps, like 360 Pano, that have been doing their thing for a while now, but Photosynth, which encourages not just wraparound, 360 degree panoramic photos but ones that let you peek up, down, and all around, too, looks and feels like it was developed by a tech juggernaut. (Which, ya know, it was.) Whereas other apps of its ilk have you do this thing where you kinda slowly and steadily smudge your way around in a circle to develop a panorama, Photosynth lets you take as many overlapping rectangular shots as you want and sorts 'em out after the fact. You don't have to follow any instructions or take them in any certain order or pattern; you just spin around, firing away. It's very satisfying. And while my first few panos weren't quite perfect—the models suffered from a few instances of mismatched stitching and had some perspectival wonkiness—they were, by and large, very very good.

Also, Microsoft, who as you may know makes their own mobile phone OS these days, has puckishly brought the Windows Phone 7 aesthetic to the iPhone app, which, man, is just really really nice. You don't realize how, I don't know, corny all these bevelled buttons and 3D animations are until you see Microsoft's flat, geometric UI on your iPhone's display. So that's a nice treat, too. More apps that look like this, please.

Photosynth for iPhone

How could it be even better?

It would be nice if you could simply share the panoramas with friends without going through Photosynth.net, a huge panorama portal that requires a Windows Live login. I'm sure I signed up for Windows Live at some point, but hell if I can remember that information. And are my panoramas then published for all to see? My bedroom is a private place that I only want to share with my close friends and every Gizmodo reader! Also, the panoramas that the app takes look great on the iPhone, but the user-uploaded content at Photosynth.net requires Silverlight and is seemingly out of reach. Why not allow users to access those through the app, too?

Photosynth for iPhonePhotosynth for iPhone | iTunes

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