Apple will break into the wearables market by incorporating sensors in headphones to measure heart rate and blood pressure, according to a posting on the anonymous app Secret.

The headphones would also use Apple's "iBeacon" system to help locate them if lost, according to the author of the post - who claims to have been let go from the company, along with others, last week.

Update: the author of the posting says it is a fake - and that he has never worked for Apple.

Apple is also working on an "iWatch" wearable, the author suggested, but said that the "name isn't final yet". That would put it into contention with Samsung, which has released both a smart watch and a "Gear Fit" wristband that claims to measure heart rate, in favour of a minimal product that could be used on millions of its existing products.

The suggestion would also fit well with leaked suggestions that iOS 8, Apple's next version of its iPhone and iPad software, will incorporate a "Healthbook" app. Those leaks, first published by 9to5Mac in March, pointed to attempts by Apple to capitalise on the growing interest in tracking fitness.

But other research has also shown that people tend to discard separately bought fitness gadgets within a few months – suggesting that any successful "wearable" would have to have a dual function, one of which was not in health or fitness-related. Apple however could have a potential market among its own users of at least 100m devices which could replace existing headphones with the newer ones.

True secrets

The nature of Secret means that it is impossible to trace the authors of posts, or verify their identity. But it has gained increasing credibility as a number of staff inside Silicon Valley companies have begun using it and leaking sometimes confidential information.

In April, one post on Secret claimed that Nike was shutting down its Fuelband wearables division - a claim that was in effect confirmed by the company. Another claimed that Google+ chief Vic Gundotra was looking at jobs outside outside Google; he left two days after the posting appeared.

More recently a claim said that Box, the enterprise cloud filing company, would delay its stock market float, and that also happened.

Ben Wood, chief of research at the research company CCS Insight, told the Guardian: "We can't take any credibility from something posted on Secret. But - are these things Apple could do? If you had simply asked me what Apple could do, then putting sensors in is a rational next step."

He points out that other companies including LG and Intel have already shown off prototypes of headphones with built-in sensors: LG's measure heart rate, and connect to a wearable band as well as a phone.

"You see so many people running with headphones in an a smartphone or music player attached," said Wood. "This is totally, utterly rational as a product direction for Apple. It's been widely investigated by other manufacturers, but as always with Apple, they're great at taking an existing technology and improving the user experience."

Samsung's Galaxy S5 includes health and fitness apps, including a heart-rate monitor which requires the user to hold a finger up to the camera.

In the post, the writer claims that "Apple's new EarPods will have sensors in them, for heart rate & blood pressure. Also iBeacons so they don't get lost. They will require the Lightning port [a proprietary connector used only on the iPhone and iPad], it's why the audio jack was moved to the bottom."

They add that "[the phone] stores the data in a similar way to thumbprint point data, fully encrypted and nothing identifiable. But nice to send to your doctor to keep track of at which point your blood pressure started rising for example."

The author also suggested that the headphones will be introduced when iOS 8, the next version of Apple's iPhone and iPad software, is released - which would probably be in September this year, to maintain the company's cycle of updates to its iPhone line too and catch the Christmas selling period, the largest in the year.

Asked why they had leaked details of Apple's forthcoming product - the sort of information the company always tries to keep secret up until the moment of an announcement - the post's author said "I have being manipulated… I'm not the only person who got sent home for good last week."

Wood noted that if the headphones do require the Lightning port, it would create a huge potential market for Apple, because was introduced with the iPhone 5 in September 2012.

Since then Apple has sold a total of 245m iPhones. A significant number of those will be the older iPhone 4 or 4S, which do not use the Lightning connector - but Apple would probably have a potential market for such "wearable" headphones of around 100m devices.

Apple said that it did not comment on rumours and speculation.

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