No Video Recording or Front Camera
While the iPhone was great for watching video in those days, you actually couldn’t use it to record video. The 2 megapixel camera on the original iPhone could produce some pretty great still photos for its era, but the iPhone hardware just wasn’t up to the task of recording even lower-resolution standard-definition video. It would actually take Apple another two years to add video recording — it didn’t appear until the iPhone 3GS arrived in 2009, although the jailbreak community was able to pull it off on older iPhone models, albeit in a pretty limited fashion that generally showed why Apple omitted it.
There was also no front-facing camera in those days — that wouldn’t appear until Apple debuted FaceTime with the iPhone 4 in 2010. To be clear, front-facing cameras weren’t extremely common on any smartphones back then, as carriers were trying to push users more toward custom “video calling” phones (with higher calling rates), but there were still apps like Skype that could have taken advantage of a front-facing camera. FaceTime, however, became Apple’s answer to video calling, and once the front camera showed up on the iPhone 4, a whole collection of third-party apps began taking advantage of it as well.