The fight to replace the iPhone and other smartphones is on - here's what to watch for in round one

Earlier this year, the biggest companies in tech all outlined their visions for the next big thing in computing. Now, things are about to get real.

When Apple holds its big event on Tuesday, it won't just be unveiling the iPhone 8, it's going to kick off another wave of announcements from the tech giants. Only this time, what the big companies will be promoting won't be their conceptions for the industry's future. It'll be the products you'll actually be able to buy this holiday season.

That transition from vision to tangible products is the first step in the master game plan of supplanting the smartphone with the next great technology platform. It'll still be a decade or more before that changeover is complete, at least if you believe Mark Zuckerberg. But we're slowly -one new Apple, Google, or Microsoft gadget at a time - building up to a future without screens, keyboards, or, indeed, the smartphone itself

If you're keeping track of the smartphone's long, slow march to history's graveyard, here are the early road signs you should be looking for the rest of the year.

Apple

At its event Tuesday, Apple is expected to launch the iPhone 8, the 10th anniversary edition of the gadget that triggered the smartphone boom. The device will represent a refresh of the iPhone's hardware; you should expect it to have a screen that covers the entire front of the phone, minus a "notch" for its camera. But more importantly, the iPhone 8 will mark Apple's first big step into the world of augmented reality.

Augmented reality is the technology that projects digital imagery into users' field of vision. It's delivered through special eyeglasses or headgear. In the future, you may access it via customized contact lenses.

Most tech industry experts assume such AR devices will eventually replace the smartphone. After all, why carry a phone if you can view your text messages, edit spreadsheets, and watch Netflix through your glasses or contact lenses?

The impending shift to augmented reality devices gives Apple almost a perverse incentive to kill the iPhone itself. Apple benefitted greatly from helping drive the tech industry's move from the PC to the smartphone, much to the chagrin of Microsoft, which ruled the PC era. It's in Apple's best interests to drive the coming transition away from smartphones to augmented reality before any upstart can slide in and turn the iPhone maker into the next Microsoft.

Apple appears to be trying to do just that. It recently launched ARkit, a set of software tools that allow developers to tap into the iPhone's camera and sensors to build augmented reality apps.

In the near term, Apple hopes ARkit will be a boon for its smartphones, and you can expect the company to heavily promote the iPhone 8's augmented reality features. CEO Tim Cook has said that with augmented reality, the iPhone will be "even more essential than it currently is."

But in the long term, ARkit could give Apple a leg up on the devices that will make the iPhone obsolete. Apple reportedly is already working on a pair of smart glasses.

When Apple launched the iPad, consumers could, from day one, download thousands of apps for it, because it could run the same ones that were designed for the iPhone, which had hit the market three years earlier. In much the same way, whenever Apple releases its smart glasses, buyers will likely be able to download lots of AR apps for them - they'll be the same ones that developers are creating with ARkit today.

But augmented reality isn't the only new post-smartphone technology or device Apple's likely to talk about on Tuesday. The company also will likely share more details on the HomePod, its new Siri-powered smart speaker, which will compete with Amazon's Echo devices and Google Home.

Google

This October, several weeks after Apple's event, Google is expected to launch the Pixel 2, its new flagship Android smartphone and the follow-up to last year's original Pixel. What will be interesting to see is if Google uses the event to talk about augmented reality.

Just recently, the company released ARcore, an augmented reality system for Android that works much like Apple's ARkit, letting developers build new apps that use the phone's camera in cool new ways. The difference is unlike Apple, whose smart glasses are still in development, Google already has some in the market in the form of the revitalized Google Glass. That could give it some momentum.

Augmented reality is arguably as important to Google as it is to Apple. As the dominant maker of smartphone operating systems, Google has a lot to lose if people start to spend more time on augmented reality devices rather than on smartphones, especially if those new devices run another company's software.

But whether or not Google reveals more of its hand in the area of augmented reality, it is likely to talk soon about digital assistants and smart speakers.

As the early success of Amazon's Alexa-powered Echo gadgets has shown, there's potentially a big market for technology that lets users ask questions and get answers without having to use a screen. At first blush, the market should be a natural one for Google. Answering questions is literally why it exists, and the thing it does better than any other company. And, indeed, Google showed last year that it was focused on the market when it released its Google Home smart speaker.

Now the company is reportedly preparing a tiny version of Google Home. Not only would the new gadget likely be better positioned than the original to compete with Amazon's best-selling and hockey puck-sized Echo Dot, it would speak to the importance to the company of its Google Assistant, the search giant's Siri-style smart agent.

But like augmented reality, smart speakers and digital assistants represent a threat to the company. It hasn't figured out how to extend its core ad business - the thing that brings in the vast majority of its revenue - to voice-based devices and interfaces.

Still, you should expect Google to keep pushing in the voice assistant market until it has significant share.

Microsoft

Every October for the last few years, Microsoft has announced new Surface computers. It's expected to do so again this year, though what exactly it will announce is still up for debate.

But we do know the company's bigger-picture strategy - if augmented reality is going to be the next big thing, Microsoft wants Windows to power it. The company doesn't want to miss out, like it did with mobile.

Microsoft staked its claim in augmented reality before the technology was cool with its HoloLens headset. Announced in early 2015 and launched with a $3,000 price tag in the middle of last year, HoloLens beat its rivals to the punch.

Now, though, Apple and Google are threatening to battle back. And so, Microsoft is going on the offensive, albeit not in augmented reality, but in a related area. The company is partnering with PC manufacturers including Dell and Asus to release virtual reality headsets for Windows at a prices as low as $300. And the software giant has struck deals with Valve and other companies to provide VR content.

The party line at Microsoft is that virtual and augmented reality are closely linked. Success in one area will lead to success in the other.

Getting back to the anticipated Surface announcement, you can expect Microsoft, when it unveils its new Surface hardware, to also tout VR on Windows.

As for voice, Microsoft is trying to build a niche for its Cortana agent as the AI system of choice for professionals on the go. You can expect to hear more from the company about how it's connecting Cortana with Amazon's Alexa. That's a tie-up that should have Google and Apple worried.

The wild card

Amazon doesn't really throw parties for itself, and isn't generally a fan of letting its plans be known in advance. But we can make some educated guess about at least one product.

For the last few weeks, the company has been offering its Echo smart speaker, which normally sells for $179, for $99 or less. That could indicate that a new version is on the way.

The whole market is keeping a close eye on Amazon, Echo, and Alexa. Because Amazon doesn't have a widely used consumer computing platform to defend, the retailer has been free to go nuts in the smart speakers and digital assistant area. So far this year, Amazon has released an Alexa-powered fashion camera and an Alexa-powered touchscreen tablet with few other controls. And numerous companies have announced that they'll be building Alexa into their products, from other smart speakers to refrigerators to cars.

Amazon's hardware business doesn't operate at the same scale as Apple's or Microsoft's, but its Echo devices are a modest success in their own right. In the race to kill the smartphone, Amazon may not be the company in the lead, but it's certainly the one to watch.

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