The pitch has always been a simple one: Place your phone down and watch it charge automatically, without the fuss of finding an outlet or connecting a power cord.
The reality of wireless charging, however, has been anything but.
Differing technologies and incompatible standards have hindered broader adoption of wireless charging. It was good enough to work in Oral-B electric toothbrushes in the early '90s, yet most phones still lack the ability to charge without a power cord.
But 2017 appears to be the year wireless charging gets its act together. You're starting to see an accelerating trickle of products incorporating the feature, from a Dell laptop unveiled at CES to automakers looking for a way to more easily power their electric vehicles. The most obvious spark could come from Apple, which appears ready to get off the sidelines and commit to the feature in a big way by joining the Wireless Power Consortium. The rumors of the iPhone 8 getting wireless charging alone are enough to get people thinking about the feature.
"Whoever Apple picks wins," said Avi Greengart, an analyst at research firm Global Data. "That's the catalyst that would drive enough volume."
Apple declined to comment on how the WPC will impact the next iPhone.
"Apple is an active member of many standards development organizations, as both a leader and contributor," the company said. "Apple is joining the Wireless Power Consortium to be able to participate and contribute ideas to the open, collaborative development of future wireless charging standards."
An embrace of wireless charging by the iPhone maker could mean a resurgence of interest in the feature. Last year, "things lost steam a bit," according to IHS analyst David Green. Yes, the number of wireless charging devices grew 40 percent year over year in 2016, but that was largely because Samsung incorporated the feature into its Galaxy S7 and Note 7 phones.
And just because wireless charging is in a phone doesn't mean consumers are taking advantage of it -- or even aware of the capability.
The market is expected to nearly double to 375 million devices in 2017. LG is the latest big-name company to embrace wireless charging, adding the feature to its Mobile World Congress trade show this week.. Wireless charging will be on people's minds as they attend the
Phone makers for years have touted wireless charging as a key feature. Nokia famously championed it with its flagship Lumia phones, and Google and LG incorporated it into the Nexus 4 phone.
Those companies used a technology called inductive charging -- the same as that electric toothbrush -- which requires you to place the device on a charging pad in a specific position.
Newer forms of wireless charging open the door to different applications. Magnetic resonance gives you a bit more freedom, so you don't have to lay your phone down at an exact spot. It can charge multiple devices with different power needs. It can also charge across a few inches and through objects, so you can mount a charging pad under a table rather than have a specific built-in inductive charger in your furniture (which Ikea actually offers).
That ability to charge over a short distance is an opportunity for automakers and their electric cars. Alex Gruzen, CEO of WiTricity, which builds chips to power magnetic resonance technology, said he's planning for car launches in 2020 that will take advantage of the technology. He sees phones capable of using magnetic resonance coming next year.
"Wireless charging is part of everyone's future roadmap," Gruzen said.
Meanwhile, companies like Energous are exploring sending power over radio frequency airwaves, similar to how online connectivity gets broadcast over Wi-Fi. In fact, Energous plans to integrate its power broadcasting capabilities into Wi-Fi routers next year.
Beyond phones, that kind of capability would be ideal for low-power sensors like smoke detectors or even smaller devices like hearing aids.
While the idea of charging something 15 feet away sounds great, there are questions about how quickly you can charge over the air. Energous also needs to get approval from the Federal Communications Commission to ensure its system is safe.
"We are quite comfortable that we have developed tech that conforms to their guidelines," said Energous CEO Steve Rizzone.
How did we get into this mess?
Here's where things get confusing.
Despite the range of technologies, the standards battles have largely been fought around two incompatible versions of inductive charging.
On one side is Qi, championed by the Wireless Power Consortium. It boasts, by far, the most wireless charging products.
On the other side is a form of inductive charging pushed by Powermat and the AirFuel Alliance, an amalgamation of two former groups that now also embraces magnetic resonance and radio frequency charging. (I told you this was confusing.)
Powermat has invested in building a network of charging stations in retail locations like Starbucks and McDonald's, but has fewer phones in the market using its technology.
Samsung actually had a chance to provide some clarity, but opted to play nice and incorporate both versions into its Galaxy S phones. That just led to more confusion, with both standards crowing about being in the high-profile devices.
"By not picking the winner, it almost prolongs the pain," Greengart said.
Talking to the two sides is like talking to a Golden State Warriors fan and a Cleveland Cavaliers fan: You're going to get two distinct realities.
"They're not there," WPC Chairman Menno Treffers said of the competition. "There's not much of a battle anymore."
"The adoption is so small now, there's no one to say what the standard is going to look like," said Ron Resnick, chairman of the AirFuel Alliance.
You can see why we're still in a logjam.
Where Apple comes in
Apple could provide some clarity. Earlier this month, it confirmed it had joined the WPC, sparking speculation that the purported iPhone 8 would include wireless charging.
It isn't just joining for show. Treffers said that Apple is expected to make a technical contribution to Qi and that company representatives were in London last week making a presentation, part of a broader gathering of members.
WPC membership doesn't guarantee that the iPhone uses Qi. Note that the Apple Watch uses a form of inductive charging too.
But if Apple commits to Qi, Powermat CEO Elad Dubzinski said his network of charging stations could support the standard with a mix of hardware and software tweaks. He said he was more concerned with managing the network of services that would flow on top of wireless charging, say, at a Starbucks.
There's also the persistent chatter that Apple is exploring wireless charging over several feet, which is where Energous could come into play. Rizzone has hinted at a "key strategic partner," which many have taken to mean Apple.
Energous has given this partner a one-year exclusivity deal for a specific product category. Given Apple's eagerness to lock up new features for itself, the deal might signal that future iPhones could embrace radio frequency charging.
And that ultimately could be the answer, with companies incorporating inductive or magnetic resonance for faster charging over shorter distances, and radio frequency to help keep your battery topped off.
No matter how things shake out, it may take Apple to light the way.
"It's a chicken-and-egg problem that can only be solved by a fruit," Greengart said.
Originally published on February 24 at 5 a.m. PT.
Updated at 5:56 a.m. PT: To include details of the G6 using wireless charging.