Of course, you can set your iPhone 4 on a tripod for stable recording, but if you also want to freely rotate your iPhone 4 for various scenes, the iPhone Swivl should be able to help you.
The iPhone Swivl is an innovative and practical camera crew designed to offer you an easy way to use your iPhone 4, iPhone 4S or iPod touch to track moving targets. As we can see from the images, the camera crew consists of two parts including a motion-tracking iPhone base and an easy-to-wear sensor. All you need to do is to dock your iPhone 4 or 4S on the base and place the compact sensor on your actor, then the gadget allows your iPhone 4 to automatically track the actor and record video. Moreover, the iPhone base also features a built-in tripod mount. Using free Swivl app, you can also adjust panning speed. Apart from that, the camera crew works well with iPhone 4/4S, iPod touch and some Android phones.
The iPhone Swivl is priced at $179 USD. If you’re interested, jump to Photojojo for more details.