With the addition of a 720p HD camera and the iMovie video editing app, the iPhone 4 is a mobile-video powerhouse. But HD video creates large files and the iPhon 4 tops out at just 32GB of storage, so the question is: how much video can you record on the iPhone 4?
The answer comes in two parts: video size and storage.
For the sake of this article, I'll assume you're shooting video at the highest-quality HD settings the iPhone 4 offers. In that case, a 1-hour video will take up about 4.73 GB of storage space on the iPhone.
Knowing that 1 hour of video take up 4.73 GB of storage doesn't quite tell you how much video the iPhone 4 can hold. That will be determined in part by what else you have loaded on the phone.
Since most users will have some apps and some music, in addition to the OS, let's assume that the average user will have at least 10 GB of content already on the phone. In that case, the iPhone 4 can hold the following amount of video:
16 GB model - 1 hour
32 GB model - 4 hours