Jailbreak Only: Safari Upload Enabler - Upload Files From Within Mobile Safari
One of the downsides to Safari for iOS is that the built-in, Apple-developed application doesn't allow users to upload content from an iPhone to a website. Fortunately, a new jailbreak tweak called "Safari Upload Enabler" allows users to upload content from within Safari itself. The tweak can be downloaded in Cydia for $1.99.