It seems Apple included a bit of a networking surprise in iOS 7. According to a logs captured from an iOS device while connecting to Apple’s Siri servers, the latest version of the mobile operating system includes support for a new technology called multipath TCP. Multipath TCP allows devices to transmit data over multiple connection types at once, such as LTE, Wi-Fi, and Bluetooth.
Essentially, this allows devices to maintain their connection to the Internet or another device even if one of the connections fails. Say for example you were on a weak Wi-Fi network that kept cutting out while attempting to watch a YouTube video. On most Internet-connected devices, that video would stop loading when your connection died, and even if it quickly reestablish a connection by finding that weak Wi-Fi signal or switching to LTE, the device would have to reopen the connection to YouTube and start downloading the video again.
With MCTCP your iOS 7 device will be able to stay connected over both LTE and Wi-Fi at once. If your Wi-Fi connection fails, the LTE connection would continue downloading the data uninterrupted. You would likely never even know the difference unless you tapped the screen and checked your signal indicator.
iOS 7 is the first commercial software to ship with a working MCTCP implementation. The technology doesn’t require any special hardware, so existing devices will be able to take advantage of this feature, too.