The combination of the new backside illuminated camera sensor and A5 processor in the iPhone 4S makes for a powerful, high-quality consumer video device that shoots full-HD.
But what if you own a device with only 16 GB of storage? That 1080p video will eat that up fast.
If you want to shoot at 720p, which is still very high quality, grab the latest version of FiLMiC Pro from the app store.
The developer has added and improved numerous features but the most important feature is the ability to determine the video resolution (or what they call the "Frame Size") before shooting.
Other features to note (which may have been added in a previous update) include the ability to select the Frame Rate, Bit Rate and audio compression options.