The future of “smart” wearable devices could be in your ear, according to the “wireless evangelist” Nick Hunn. Hunn is working on a new market forecast report for wearable tech, and wrote in a preview that he expects “hearables,” or smart earbuds, to be worth over $5 billion by 2018. For context, a recent forecast (pdf) predicted a total market of $30 to $50 billion for wearables by that year. Here’s why he could be right:

Screens make things complicated

After the release of the futuristic romance movie Her, in which the main character falls in love with an artificially intelligent operating system who speaks to him mostly through an earpiece, the production designer KK Barrett told Wired that he’d banished most screens, and basically all physical interaction with computers. “We decided we didn’t want to have physical contact,” he said. “We wanted it to be natural. Hence the elimination of software keyboards as we know them.”

The effect is a simplification of user interface with software: People would ask for what they wanted in the same way they’d ask another person, and their smart devices would deliver. Wrists could stay bare, and actual cellphones would hardly ever emerge.

Google wants to make voice control as seamless and easy to use as a keyboard. Right now, the interface is being groomed for use with Google’s first smartwatch. But after it overcomes the challenges of making a tiny screen functional, it can move on to working without one.

The technology is already in progress

This isn’t Google’s only product in development that could help hearables happen. The company’s Moto X “superphone” is able to listen for voice commands constantly—even when it’s asleep. The chips that allow this constant listening does so with very little power.

But for voice recognition to be appealing, it has to be quicker. Most voice recognition requires an internet connection—even if you’re not asking your phone to search the internet. When you ask Apple’s Siri to open iTunes, for example, your command goes to the cloud for interpretation. The delay of a few seconds is enough to make voice commands impractical for a lot of tasks. Intel thinks it has the solution: It has plans for an offline alternative, allowing for faster responses. Intel’s head of wearables, Mike Bell, told Quartz earlier this year that the company will make a processor powerful enough to parse out voice commands on its own—and small enough to fit on a wearable.

Intel is partnering with a third party to make a wireless headset that connects to your smartphone. Called Jarvis, it’s expected to behave like its Iron Man franchise namesake: The headset will understand your voice commands and respond to them verbally.

Your ear is a better home for a fitness tracker than your wrist

“Few people realize,” Nick Hunn writes in the preview of his market forecast, “that the ear is a remarkably good place to measure many vital signs.” It doesn’t move around like the wrist does, which will make readings like heart rate, blood pressure, temperature, and pulse oximetry more accurate. Several companies are already exploring the potential for health sensors in the ear: Dublin-based Zinc Software is raising money to make a hearing-aid-like clip-on that monitors heart rate for biofeedback purposes, and iRiver has a set of workout headphones that capture movement and heart rate. Apple recently filed a patent for earbuds that capture biometric data, as well. Maybe Jawbone’s next health and fitness tracker should look a little more like one of its Bluetooth earpieces.

We’re used to having stuff in our ears

One of the biggest barriers faced by all wearables is social acceptance. We’ve grown used to staring down at our phones in lots of public places—and even in more intimate settings. But something about the idea of a constant division of our attention—by way of a visual interface like Google Glass, for example– still bothers many of us. If you’ve been outside anytime in the past five years or so, you already know that earbuds have overcome that problem. We’re used to our peers listening to music constantly or shouting into their headphone cords as they walk down the street. So having a constant connection to your personal audio assistant won’t look out of place.

It can start with music

To break us into the concept, hearables can make our music listening experience smarter. Intel has previewed a set of heart rate-tracking headphones that pick your music based on your running pace. When you slow down, your music will push you to go faster.

But there’s room for even smarter music: Cone, a smart speaker coming out this summer, will act as a full-service music curator that learns your music habits and predicts your every auditory whim. Now imagine how great it would be if Cone fit into your ear, instead of sitting on your counter. Obviously it’s a tall order to shrink a new device so quickly; but who wouldn’t want a smart, in-ear jukebox?