UPDATE:Wow, this story certainly morphed quickly into something totally different. So the story goes is that an iPhone with a cracked screen -- not an iPhone 4 -- was used just for the GPS MobileMe functionality. The real camera work was done Go Pro Hero HD.
People take their phones with them everywhere, but one guy and his son sent their iPhone 4 into space and had it capture the HD video of the experience both upwards and downwards.
Luke Geissbuhler of Brooklyn, NY built a housing for the iPhone 4 that would help it withstand the extreme conditions of the journey into the atmosphere (including simple solutions such as hand warming-packs to prevent freezing) and attached it to a simple weather balloon.
The homemade solution travelled 19 miles high before the balloon popped and the iPhone 4 rushed back to earth at 150 miles per hour.
While there are other devices that can record HD video, Geissbuhler likely chose the iPhone 4 for the MobileMe GPS tracking feature so that he could easily recover the phone once it was back to ground level.
Check out the video below. It's fun if you're into geeky space projects.
Source: Brooklyn Space Program