The 3.5mm headphone jack might go away one day, but there's plenty of power there today!
While rumors persist the iPhone 7 will go 3.5mm headphone jack-free, Apple's done a lot to make the very old port as useful as possible for all of their devices. The EarPods that come with your iPhone or iPod touch can be used to control a wide range of features, including music, calls, and even Siri. So can any other set of headphones, from Beats to Bose, and on iPad as well—as long as they integrate the remote and mic hardware. The remote controls are great for accessibility, but they're also great for convenience. What's more, they also work with the Mac!
If you're not familiar with all the options, here's a complete list!