After being introduced during his keynote address at WWDC 2010 earlier this month, Apple CEO Steve Jobs quipped that iMovie for iPhone will be available alongside the iPhone 4 “if we approve it.” And approve it they did -- iMovie is ready to rock your new iPhone 4.

Apple’s App Store elves were busy overnight in preparation of Thursday’s iPhone 4 launch, including the release of iMovie for iPhone. The new app promises to complement the new handset’s 720p HD movies, allowing you powerful editing tools in the palm of your hand.

“Make beautiful HD movies anywhere with iMovie, the fun, feature-rich video editing app for iPhone 4,” the app’s description reads. “Create a video postcard of your day at the beach and publish it to the web -- without ever leaving your spot in the sand. Or make a movie of your child’s birthday party and sent it to your parents -- while the party is in full swing. With iMovie for iPhone, you can start several projects and finish them whenever you want and wherever you are.”

Unfortunately, the diminutive iMovie is strictly for new owners of the iPhone 4 -- it doesn’t work with prior devices, including the iPhone 3GS, despite that handset’s ability to record lower-resolution video.

Among the features touted by iMovie for iPhone are full multi-touch controls -- tap to add or record video right into your project, drag to trim the lengths of video clips and photos, pinch to zoom the timeline and get a closer look, or slide to scrub through the video in your project. Five included themes will help give your project a polished look with ease, including titles and transitions.

As touted by Steve Jobs during the keynote announcement, iMovie is also capable of adding music and photos from your iPhone 4, and when the whole project is done you can easily export it in one of three sizes (Medium, Large or HD), including straight to your MobileMe Gallery or YouTube, or via an e-mail or MMS message.

iMovie for iPhone is available now for $4.99; the 30.6MB download is only compatible with the iPhone 4 running iOS 4.

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