Qik, the streaming video software for mobile phones, has launched an iPhone 3GS application which is now in the App Store. Much like Qik applications for other handsets, it lets you record video, geotag it, and then upload it to the web when you're done.
However, unlike Qik applications for other handsets, you can't live-stream video from the iPhone 3GS, and - most cripplingly - doesn't work on 3G, instead requiring a Wi-Fi connection. A Qik app for jailbroken iPhones provides functionality for both those things.
The official app does let you share content across social networks, but is unlikely to gain the same popularity as versions on other handsets, as it's lacking the core streaming functionality. Still, if you want to have a play with it, it's free, and can be found in the App store now.