We're still finding new things from Google I/O 2014. Last week something called Multi-Networking was announced, but it wasn't really hyped. It's a pretty big deal, though. Switching Wi-Fi and data connections is about to get much easier with Android L.
Multi-Networking is a new API that will allow developers to add in this simple, yet powerful, new feature to their Android apps. I say new, but the feature itself isn't really new. Old-school Nokia Symbian devices had this same feature, but current gen BlackBerries and Windows Phone devices don't. Multi-Networking will allow your device to connect to, and maintain, multiple network connections at the same time. For users, this is handy in situations where you're connected to a Wi-Fi network but need to do something that requires a cellular connection, like sending MMS messages. This feature will also make data handoffs seamless, like when you're on a Google Hangout or VoIP call and need to switch between cellular and Wi-Fi networks. This is not a really flashy feature, but it's one of those things that can make the user experience much better, all behind the scenes.
Android hasn't had this feature previously, mostly because of the impact on battery life that maintaining several connections can have. With the advent of larger screens came much larger batteries, and along with as the improvements and optimizations on the software side, you shouldn't see a major impact on battery life from apps that have this API properly implemented. That's not to say it won't have an impact. Devs will have to make sure that their app doesn't have Multi-Networking enabled all the time, but in those situations where it's warranted, it will be a big improvement.
If you're a developer, you can find more information about implementing the new API here. Google talked a little about Multi-Networking at an I/O session, too. You can watch that video down below. This is seriously a big deal, you guys.