According to KGI analyst Ming-Chi Kuo, the iWatch will offer biometric functionality (more on this later), an NFC chip (which seems unlikely given the fact that Apple has steered away from NFC in favour of iBeacon), and a 200 to 250mAh battery, along with integration with all your Apple products. He also thinks it will have a "fashionable appearance", and a slim and light design. This leads him to speculate that Apple will be competing with high-end watch fashion brands in the long term (five to ten years). We look at some of the features that might be offered by the iWatch below...

iWatch rumours: Display

It's been suggested that the iWatch will come in two sizes, a larger one for men and a smaller one for women.

Kuo predicts that the iWatch will come in two sizes with screens at 1.3in and 1.5in and suggests that the screen will be flexible AMOLED display. Expect to see sapphire crystal glass too for durability and scratch-resistance.

According to Reuters in a report published in June 2014, though, the face of Apple's iWatch will measure 2.5in diagonally. The publication cites unnamed sources familiar with the iWatch, who say that the touchscreen display will protrude from the band of the device and that it will charge wirelessly.

On the same day, The Wall Street Journal published a report to say that there will be multiple designs of the iWatch, to appeal to a variety of potential customers.

Research firm DisplaySearch has suggested that the iWatch could use an AMOLED display technology, with a flexible 1.3in or 1.5in display with a 320 by 320 pixel resolution equating to a pixel density of 348 ppi or 278ppi.

Alternatively, a separate rumour from Korea's Digital Daily suggests LG will be making 1.52in flexible P-OLED displays for the iWatch, with production set to begin in the second half of 2014.

The NYT claimed that Apple's wristwatch would be made of glass that can curve around the human body.

Further speculation that arrived in April 2014 also suggests that the flexible OLED displays for Apple's iWatch will be made by LG. That's according to Korean publication Naver, which also believes a 1.3in and 1.5in iWatch is in the works.

In June, Nokia's Semiconductor Energy Lab unveiled a new folding OLED display, (above), a technology similar to that which Apple is expected to use in the iWatch.

Apple has confirmed that its new Arizona factory is going to be used for sapphire manufacturing, and, while most rumours suggest it'll be used for displays for a bigger iPhone, some reports suggest the iWatch could have sapphire displays that are made there.

Former Apple designer Bruce Tognazzini has said in a blog post that the iWatch's value will be "underestimated" at launch, but will "grow to have a profound impact on our lives and Apple's fortunes."

Then, in June, Apple won a patent for a curved battery that could be used for the iWatch.

Siri to play key role in iWatch control

Speculation that arrived with March suggests that Apple is working to open up Siri to developers, to enable integration with third-party apps. It's believed that Siri will be a key feature of the iWatch.

That's according to The Information, which claims Siri is being improved to bring the ability to carry out more advanced functions including booking a hotel, for example.

"The technology being developed at Apple can also be applied to determine what app to show a user when they have limited screen space, as they would when using a smartwatch the company has been developing, according to people familiar with the effort," The Information explains in its report. "If a user starts running, for example, Siri might show them a fitness app that could help them track their workout while moving other apps into the background."

At WWDC 2014, Apple announced that Siri would be getting some improvements later this year, including the ability to say "Hey, Siri" to activate the assistant, rather than having to press a button, so this would work well with the iWatch. 

At the end of June, Wired reported that Apple has hired a big, impressive group of speech recognition experts from Nuance, the company behind the technology that powers Siri, who'll work to make Siri understand you better. This also indicates that Apple is serious about voice recognition, possibly due to its importance for the iWatch.

iWatch will have wireless charging capabilities

On 2 February, the New York Times published a report that suggested Apple's iWatch will have inductive wireless charging technology, as well as a curved display and maybe even solar panels.

The report cites people familiar with the project, who say Apple is investigating ways to make its iWatch energy efficient. "Apple has been testing a method to charge the battery wirelessly with magnetic induction," the report reads, pointing to similar technology used in Nokia's Lumia 920. 

NYT also suggests that Apple has been experimenting with ways to charge the iWatch battery using the movement of the wearer's arm. An Apple patent filed back in 2009 covers such technique, which involves pushing power generated by the swinging of a persons arm into the device's battery.

A new rumour that surfaced in February suggests Apple is looking to use a new, layered lithium-ion battery from LG in the iWatch. The rumour comes from source cited in a Korea Herald report, which claims the shapeable battery can last for up to 16 per cent longer than current lithium-ion batteries of a similar size.

iWatch will work with Health and Healthkit in iOS 8

As expected, Apple introduced a health and fitness tracking application with iOS 8 during WWDC 2014. It's likely that the Health app will work closely with the iWatch's biometric sensors, to collect data such as how many steps you've taken, how many calories you've burned and the distance you've walked. The app will also allegedly be able to monitor blood pressure, hydration levels, heart rate and more.

The Health app arrives alongside reports that Apple executives have been meeting with medical officials including the Food and Drug Administration. Apple has also hired several people from the medical field, as mentioned above. (On a related note, Tim Cook is known to be an admirer of the Nike Fuel band, an established piece of fitness-monitoring wearable computing tech.)

Apple could use technology similar to the M7 chip found in the iPhone 5S to further health monitoring capabilities, which would work with iPhones and iPads running iOS 8.

MobiHealthNews's Brian Dolan claims to have spoken to sources with "limited but direct knowledge" of Apple's iWatch plans. He says that the iWatch will not act as a standalone device – it will require iPhone or iPad connectivity in order to work fully. He also believes that the rumours about the Healthbook app are true, and that the app will focus on exercise, diet, sleep, stress, medication adherence and women's health, but believes that the name may be incorrect and doesn't expect the rumoured "hydration monitoring" feature to come to light.

Apple has also allegedly been exploring technology that can help predict heart attacks.

A patent published by the US Patent and Trademark Office in June reveals that Apple has been working on technology that could be used as a weightlifting tracker in the iWatch.

The aforementioned testing from professional athletes also indicates that Apple is serious about making the iWatch fitness focused.

iWatch rumours: Health ID

Further to the Health app for iWatch rumours is speculation that Apple could use the sensors in the iWatch to create 'Health ID,' which could scan your heartbeat in order to identify you, and therefore act as a security measure that works with Touch ID for mobile payments.

You can find out more about the idea of Health ID here.

iWatch rumours: Apple and Nike partnership

It has recently been reported that will no longer be continuing its FuelBand, the fitness-tracking device that could have been a big rival for the iWatch. Nike is believed to have fired as many as 55 members of its Digital Sport hardware team as a result of the decision, and Nike has confirmed that a "small number" of layoffs did take place.

After puzzling over the news, several reports suggest that the move may be due to a partnership with Apple for the iWatch.

This is certainly not a daft suggestion. After all, the FuelBand only worked with iOS, Apple CEO Tim Cook is also on the board of directors at Nike, and Apple recently poached former Nike wearables boss Ben Shaffer.

Plus, a Nike spokesperson recently told The Next Web: "Partnering with industry-leading tech companies is nothing new for us. We have been working with Apple to develop products since 2006, when we introduced Nike+ Running, and Nike has since created iOS Apps including Nike+ Training Club, Nike+ FuelBand and Nike+ Move.

"Building on these successful products and services, Nike and Apple continue to partner on emerging technologies to create better solutions for all athletes."

Plus, Nike CEO Mark Parker has said that he is "excited" about the company's relationship with Apple. During an interview about the FuelBand on CNBC in April, Parker said: "We have partners we work with. Obviously the most visible partner we have is Apple. We've been working with them for a long time. And we're excited about where that relationship will go forward."

Interviewer Sara Eisen then said: "Well, can you give us a hint? Are we going to expect some of collaborative device coming out? Nike and Apple?"

"I can't really say that," Parker replied. "There's been a lot of speculation, which I understand. I will just say the relationship between Nike and Apple will continue. And I am personally – as we all are at Nike – very excited about what's to come."

However, Nike has said that the Nike+ FuelBand SE "remains an important part of our business" and that it will "sell and support the Nike+ FuelBand SE for the foreseeable future."

The iWatch will run iOS 8

The New York Times has suggested that the iWatch would operate on Apple's iOS platform. This would enable developers to create apps for the device, and Apple could also include its own apps in the iWatch, such as turn-by-turn walking directions and Find My iPhone.

You can find out more about iOS 8 here.

Image Credit Martin Hajek

The iWatch will have music features

It seems likely that Apple will incorporate some sort of music feature into its iWatch, what with the popularity of iTunes. The device could act as a controller for an iPhone to enable users to choose tracks, rather than storing music itself.

iWatch leaked images

There are currently no leaked images of Apple's iWatch, but several designers have come up with concept illustrations and mockups to demonstrate what such device could look like. Some of those images are dotted through the article above, so scroll up to see the rest if you missed them.

An impressive new concept from user interface designer Todd Hamilton imagines an iWatch that takes design cues from both the Nike Fuelband and Apple's iPhone (you can see this concept video near the top of this article).

"I kept the band simple with a curved touchscreen display on the front," says Hamilton. "For physical controls I placed a single button on the left to act as the Home button, and two more on the other side for volume controls."

"For the lock screen I designed a simple black & white interface displaying the time, date and button to activate Siri. From here the possible actions are: tap to use Siri, swipe up to unlock, or pull down to view Notifications. Sound familiar? While I was designing this I found myself pretending what it would be like to use swiping gestures on my wrist. Give it a try, it feels pretty good!"

In March, a new render that shows a solar powered iWatch hit the web. It's designed by Jermaine Smit, and shows a device with an edge-to-edge curved touch display, and a 2.1 megapixel camera.

A second new concept to arrive in March is by design student Tomas Moyano, who has envisioned a circular iWatch (below) that's customisable and waterproof, and uses vibration alerts. It charges using solar panels.

Following the launch of the iPhone 5s and iPhone 5c, designer Martin Hajek worked with Mac User's Adam Banks to create matching iWatch concepts. See more by going to Martin's website.

ADR Studio has created the 3D rendering of a possible iWatch as shown below. Click here for the full gallery. The studio also created some of the other images shown throughout this article.

 

Ciccarese Design created a concpet of the iWatch too, which sports a sleek, Apple-esque design and iOS 7.

Finally, Yrving Yorrealba came up with this transparent iWatch design, which he calls the 'iWrist'.

 

The only image that could constitute as a 'leaked image' is this one (below) that is believed to be a screenshot of iOS 8 running on an iPhone. Look closely, and you'll spot the Watch Utility app. We know that this screenshot is not completely accurate, though, as the Health app in iOS 8 has now been revealed and looks different to the one shown here.

What do you think about the idea of an Apple iWatch? Let us know in the comments section below or on Twitter.

iWatch rivals - what smartphone competition will Apple have?

Some companies have previously experimented with wearable technologies, including watches. Microsoft, for example, launched a smart wristwatch around a concept called Smart Personal Object Technology it unveiled in 2002, but withdrew it after a lacklustre performance.

Toshiba also unveiled a prototype smartwatch that can pair with an iOS or Android phone and provide notifications during CES this year. The watch can alert users to calls, emails and calendar notifications, and can pull in news, weather, or GPS directions. It can also recognise the user's pulse pattern to disable the smartwatch's functions should a thief attempt to access it.

Other similar devices already on the market are the Pebble, Nokia and Fossil Bluetooth 4.0 watches, and the Sony SmartWatch that pairs with Android devices. A Bluetooth smartwatch was also demoed by Martian Watches at CES in 2013.

See: 11 iWatch rivals compared in our wearables round-up

Apple's biggest rival, Samsung, launched its Galaxy Gear in 2013, but the device was deemed a flop by many. However, the second iteration of the Galaxy Gear arrived in February 2014 and it seems to have had a much better reception so far.

In addition, Foxconn, a major supplier for Apple, is believed to be working on its own smart watch.

Cantor Fitzgerald analyst Brian White has said that he believes the wearable tech market won't reach a "meaningful" level until Apple's iWatch arrives.

In January, white said in a note to investors that he thinks wearable devices have become a "legitimate, new product category." However, he doesn't expect "meaningful adoption" of wristworn smart devices until Apple enters the market.

2014's CES seemed to be the year of wearable tech, with numerous companies revealing new ventures into the market. Apple could learn a lot from the market, including the five lessons pointed out by Macworld's sister site TechHive, which include: The activity tracker space is painfully overcrowded, smartwatch vendors still don't get design and wearable tech is still incredibly exciting, despite its stumbles.

The, in March 2014, Google announced a 'preview SDK' for its new Android Wear platform that has caused a bit of a buzz among the technology industry and could certainly mean many new, strong competitors against the iWatch.

We imagine that Apple is learning from the current market and its failures, and will only launch its iWatch if and when it becomes something that people will be amazed by.

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