Apple has alreadypushed the use of its mobile devices for health tracking andmedical research, and recently added a feature that can connect tosome hospital medical-records systems. (Photo: David PaulMorris/Bloomberg)

Apple Inc.'s new watch is the latest proof: Big Tech is tryingto remake health care in its own image.

The device, introduced at a splashy launch event last week, cancall for help after a fall. It can monitor heartbeats for dangerous conditions. It can do anelectrocardiogram, a test that monitors for a common abnormal heartrhythm and is usually done by a doctor.

For the iPhone maker, it's the boldest foray so far intopersonal health. Apple has already pushed the use of its mobiledevices for health tracking and medical research, and recentlyadded a feature that can connect to some hospital medical-records systems.

Related: 12 biggest names in health caredisruption

With iPhones and other mobile devices in the hands of morepeople than ever, the stakes couldn't be higher. Tech giants suchas Apple, Amazon.com Inc., Microsoft Corp. and Google have tofigure out, now that they are among the biggest companies in theworld with some of the world's most ubiquitous brands, how toget even bigger.

The business of keeping people well is a logical frontier.Health care accounts for about 18 percent of U.S. economic outputand still often relies on antiquated tools like fax machines,making it an enticing opening for tech behemoths looking for newterrain to conquer.

Already, the companies are in deep. Apple is tracking vitalsigns. Amazon bought its way into the pharmacy business whilejoining with two powerful partners to remake worker healthcoverage. Google parent Alphabet Inc. wants to help make you livelonger.

There are reasons for skepticism. Apple's new pulse-monitoringtools could trigger false positives and panics, some analystsworry. Amazon and its partners hired a famous surgeon CEO for theirworker health plan, but building it out could take years.

Still, the companies are moving ahead at breakneck speed. It canbe hard to keep track of developments. Here's where thingsstand:

Amazon has its tentacles everywhere. It's working on theemployee-health venture with JPMorgan Chase & Co. and WarrenBuffett's Berkshire Hathaway Inc. Earlier this year, it paid $1billion for online pharmacy PillPack after months of speculationabout its plans to shake up the prescription-drug business.

Meanwhile, hospitals, doctors and dentists' offices have helpedpropel Amazon Business to $10 billion in annual sales. The unitsells everything from latex gloves and patient bed liners tospecialized dental tools and medical devices. Customers includemore than half of the 100 biggest hospital networks in the country,the company said Wednesday.

Amazon Web Services, the cloud-computing division, offers toolsthat can be used to move from paper to electronic medical recordsand help genomics researchers store and analyze vast amounts ofdata. Cloud computing lets customers ramp up processing power fortrials and modeling only when they need it, allowing them toconduct tests more cost-effectively.

One, called Calico, has a team of biologists, doctors and drugdevelopers that are focused on understanding the process of aging,with the very Silicon Valley goal of extending life spans. Thesecond, Verily, is working on new ways to collect and use healthdata, such as a contact lens that monitors glucose levels.DeepMind, Google's main artificial-intelligence company, also has asignificant health-care division.

Additionally, Google has special cloud storage, email andfile-sharing products that are HIPAA-compliant. Google Fit is asuite of tools for Android phones that developers can use to buildhealth-tracking apps, just like Apple Health. And don't forget thecore search product. The company has been working to improve “Dr.Google” ever since people typed “what does a heart attack feellike?” into their browsers. Google now has a special team ofdoctors who help make sure results for common questions offeraccurate information.

After Microsoft axed a fitness band and sold an earlierhealth-software group to General Electric Co., the software giantis trying to sell hospitals, drugmakers and doctors software, cloudprocessing and artificial-intelligence services for morepersonalized medical care.

The company has demonstrated speech- and language-recognitionsoftware for a “triage bot” and unveiled tools for monitoringwhether a patient sticks with a treatment plan that work withrivals' fitness trackers. Microsoft's Azure cloud-computing serviceis working with St. Jude Children's Research Hospital to harnessthe processing muscle of the cloud for computing-intensive geneticanalysis.

Microsoft's research labs are also looking into how to usemachine learning to better target cancer therapies and to detectcancers or other potentially fatal medical conditions earlier.

Ride-hailing unicorns Uber Technologies Inc. and Lyft Inc. arealso seeking a slice of the health-care pie. The companies saybeing able to summon a car for patients makes them more likely toshow up for appointments.

Beyond big tech, General Electric, the old-school manufacturerof lightbulbs and jet engines, is a major player in themedical-device space. Its health-care arm, which is expected to bespun off into a stand-alone company, makes everything fromcloud-connected MRI scanners to artificial-intelligence software towireless fetal monitors.

— With assistance by Rick Clough

Read more about the influence of the tech industry onhealth care:

• Birth control app popularity a sign of a fertilehealth tech market
• Can apps slay the medical billdragon?
• Tech giants pledge to reform health caredata

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