In a short note to developers, Apple says that they can now submit binaries of up to 4 GB of application via iTunes Connect. Since the App Store started in 2008, this limit had not moved and so far remained at 2 GB.
The apple company has therefore decided to double the bet to allow developers to include more media content when submitting an application. Video game developers should be particularly sensitive to this new upward limit.
The binaries for an iOS application contain the executable file as well as all the images, audio and other content gathered in a single file which we understand that depending on the targeted domain can be overweight. Not to mention that you have to think about compatibility with several iOS terminals.
Still, the storage of some iOS terminals is not expandable and 4 GB … this can be prohibitive. Note also that despite the advent of 4G, Apple retains a cell phone download limit of 100 MB. For more, it's via Wi-Fi.