Unconfirmed speculations posit that Apple, at least for Verizon Wireless, will be delivering iOS updates over the air in iOS 5. This will be a new change for iPhone, and potentially iPad and iPod Touch, owners as currently Apple requires users to tether their smartphones and devices to a computer to download and install the update via iTunes.
By pushing out and allowing over the air, OTA, delivery of the latest iOS software, Apple will be able to more effectively compete with Google’s Android OS and will help to ensure that its customers will always be running the latest version of iOS.
Currently, the large size of iOS software updates run between 500-700 MB. However, these updates include the full OS images along with the relevant patches and features in the latest builds. If Apple will be delivering OTA updates, it will need to break out the core OS from the patches as carriers will probably not want users to download 500 MB on their networks. This way, only the patches will need to be downloaded and installed, rather than a complete install of the entire mobile OS.
Sources to 9to5 Mac say that the feature will come after iOS 5, meaning that for iPhone owners, iOS 5 will still be a tethered update process. After iOS 5, if there is a patch, it could potentially be delivered OTA.