How Apple Watch Series 8's Body Temperature Feature Is Expected to Work

[MacRumors]

Body temperature sensing technology is believed to be the headline upgrade offered by the Apple Watch Series 8 when it debuts at Apple's "Far out" event next week. Thanks to a variety of reports from reliable sources, we have a fairly good idea of how the body temperature health features are expected to work.

The Apple Watch Series 6's rear sensor array that introduced blood-oxygen sensing.​

Body temperature monitoring for the Apple Watch has long been rumored by sources like Apple analyst Ming-Chi Kuo, but over the past year rumors have crystalized around the feature finally debuting on the Apple Watch Series 8 later this year. Contrary to the hopes of some observers hoping to be able to check their body temperature or get notifications if they have a fever, it looks like the feature may be significantly more limited at launch.

Reports from the Wall Street Journal and Bloomberg's Mark Gurman state that the body temperature sensor is primarily designed to aid fertility planning, giving women insights into their ovulation cycle, and could be used to improve the detection of patterns when tracking sleep. Apple significantly bolstered the Apple Watch's sleep tracking capabilities in watchOS 9, so further improvements in this area aided by hardware this year seem plausible.

MacRumors Apple Watch concept depicting exact body temperature reading capabilities, a feature that is unlikely to be present on the Apple Watch Series 8.​

Apple is also said to have plans to enable the body temperature sensor to detect when a user has a fever, but it seems unlikely that this feature will be available upon the launch of the Apple Watch Series 8. Gurman believes that further in the future, Apple Watch models could determine if a user has a higher than normal body temperature, but it is still unlikely to show an exact measurement. All in all, this suggests that the body temperature sensor that comes with the Apple Watch Series 8 may not be quite what some users have come to expect.

According to Kuo, Apple originally intended to offer a body temperature measurement feature with the ‌Apple Watch Series 7‌ models, but the company shelved the plans when the body temperature algorithm it had developed failed to meet requirements before the device entered the engineering validation testing (EVT) phase last year.

The problems Apple has experienced relating to body temperature measurement purportedly relate to the fact that skin temperature quickly varies based on the environment, and since a smartwatch cannot monitor core body temperature using hardware, the feature is heavily dependent on an algorithm that produces accurate results. This likely explains why the body temperature sensing capabilities of the Apple Watch may be limited when the Series 8 launches later this year.

Last month, the United States Patent and Trademark Office granted Apple a patent for a temperature sensing system conspicuously related to the Apple Watch, including a "high-precision and high-accuracy absolute temperature sensor." Apple's patent protects an electronic device housing that encloses a temperature sensing system comprising a temperature sensor and a differential temperature probe.

Illustration from Apple's "Temperature gradient sensing in electronic devices" patent filing.​

The system works by calculating the difference between two ends of a probe. One end touches the surface to be measured, while the other is connected to a temperature sensor. The voltage delta across the different ends of the probe can then be correlated to a differential temperature measurement.

It is not clear if the exact technology outlined in the patent is related to the body temperature sensor that is expected to be used in the Apple Watch Series 8. It is also possible that Apple plans to use a proprietary system from Rockley Photonics, a British health technology startup that has created a sensor system designed for wearable devices that includes a core body temperature sensor.

Rockley Photonics' advanced digital sensor system.​

Last year, it was revealed that Apple is the largest customer of Rockley Photonics. Rockley's financial filings said that Apple accounted for the majority of its revenue over the last two years and that it has an ongoing "supply and development agreement" with the company, under which it expects to continue to heavily rely on Apple for most of its revenue. Rockley previously said that it expects its technology to be used in consumer smartwatches in 2022, which could align to the launch of the Apple Watch Series 8.

Beyond a body temperature sensor, the Apple Watch Series 8 is expected to feature the S8 chip and a Low Power Mode to prolong battery life. The device is highly likely to be unveiled at Apple's event on Wednesday, September 7.

Article Link: How Apple Watch Series 8's Body Temperature Feature Is Expected to Work

 

[ct2k7]

So the primary use is limited to around half of the population at launch and potentially new headlining usage later?

From an upgrade perspective, it’s probably wiser to go with a series 7 if once doesn’t have it than an 8 at this point? What else does the Series 8 offer?

 

[willyx]

Sounds like a super useful feature

/s

 

[tobybrut]

If they do anything with the body temperature sensor, it'll be more than the Samsung Galaxy Watch5/Watch5 Pro, which also includes a body temperature sensor. On the Watch5, it currently has no purpose. The only thing Samsung says about it is that they're working with other companies to use it, but it's useless right out of the box.

 

[ian87w]

Most accurate body temp is measured rectally, so I expect accessory dongles for the new Apple Watch.

 

[Unami]

Well that was pretty much expected, that this will only be kind of an anomaly-detection feature. Exact body-temperature measurement is probably a feature for future airpod pros.

 

[TVreporter]

I can see the next ad… opens with someone lying in bed sounding congested

cue a Foreigner song starts

“Well I’m hot blooded…
“Check it and see…

(Zoom into the watch) and it flashes

“I’ve got a fever of 103…”


Voiceover: Apple Watch 8… just what the doctor ordered.

 

[ct2k7]

If they do anything with the body temperature sensor, it'll be more than the Samsung Galaxy Watch5/Watch5 Pro, which also includes a body temperature sensor. On the Watch5, it currently has no purpose. The only thing Samsung says about it is that they're working with other companies to use it, but it's useless right out of the box.

Out of the box, if the article is true, it’s also useless for about half of the population.

 

[Graham Caracas]

If you trust your health to an overpriced disposable watch, this is the one to get.

 

[TVreporter]

Most accurate body temp is measured rectally, so I expect accessory dongles for the new Apple Watch.

Schiller: “Can't innovate anymore, my ass!”

 

[Greenmeenie]

Just put your hand on your forehead to check for a fever like your Mom used to do. 😉 I think a glucose monitor would be a more worthy upgrade. But that doesn’t look like it’ll happen for awhile. I won’t be upgrading my Apple Watch 6 anytime soon. i’m very active, and It does everything I need or want In a health watch.

 

[Eldaerenth Faexidor]

It’s a bit of a downer if this new feature only works for half the population. Most people look for a valid reason to upgrade and buy a new Apple watch, this would be a valid reason not to upgrade. Let’s first see what they’ve created for us.

 

[stevet]

MacRumors Apple Watch concept depicting exact body temperature reading capabilities, a feature that is unlikely to be present on the ‌Apple Watch Series 8‌.

But we're going to post it anyway...

 

[satchmo]

So the primary use is limited to around half of the population at launch and potentially new headlining usage later?

From an upgrade perspective, it’s probably wiser to go with a series 7 if once doesn’t have it than an 8 at this point? What else does the Series 8 offer?

It would likely be longer battery life. Along with the body sensor, a marginally faster processor, and new colours, it doesn’t seem like much of an upgrade. But we shall see and I hope to be surprised.

 

[1rottenapple]

Out of the box, if the article is true, it’s also useless for about half of the population.

Dare I say, discriminatory! Haha bummer low power mode seems to be a s8 only feature. Not sure if that’s worth it. Will want to see cellular reviews on low power mode if available for me to consider the upgrade.

 

[JMStearnsX2]

Rockley's financial filings said that Apple accounted for the majority of its revenue over the last two years and that it has an ongoing "supply and development agreement" with the company, under which it expects to continue to heavily rely on Apple for most of its revenue.

This is bad news for this poor company, Apple has a history of sherlocking companies' features and tech, then leaving them high and dry. I'm willing to bet that Rockley will be bankrupt soon.
Such a shame.

 

[Mitochris]

I would prefer that they focus on extending battery life to days/weeks, rather than introduce features that are poof limited application.

 

[arkitect]

Most accurate body temp is measured rectally, so I expect accessory dongles for the new Apple Watch.

Schiller: “Can't innovate anymore, my ass!”

Well played! 😄

This is bad news for this poor company, Apple has a history of sherlocking companies' features and tech, then leaving them high and dry. I'm willing to bet that Rockley will be bankrupt soon.
Such a shame.

My thoughts exactly. All the eggs in one fickle Apple basket...

 

[canyonblue737]

This isn't new tech folks. Garmin, Fitbit, Whoop, and others have had it for years. You can NOT determine internal body temp from skin temp, there are too many variables... temp of the room, temp when you are outdoors etc. which all affects the temp of your skin. What these devices usually do is measure skin temp AT NIGHT when you appear to be sleeping because that tends to be most consistent night to night (but still varies if your room temp varies). It uses this data to pretty good effect for fertility and cycle planning for women and also to alert to POSSIBLE fevers. It's surprisingly accurate for these two things on other devices and I imagine it will be for Apple too. I suspect since many don't wear their Apple Watch to bed that Apple has tried to make this all work with many measurements taken throughout the day which makes the whole thing more difficult but I'm sure they have all kinds of machine learning and algorithms that will make it possible.

 

[ct2k7]

This isn't new tech folks. Garmin, Fitbit, Whoop, and others have had it for years. You can NOT determine internal body temp from skin temp, there are too many variables... temp of the room, temp when you are outdoors etc. which all affects the temp of your skin. What these devices usually do is measure skin temp AT NIGHT when you appear to be sleeping because that tends to be most consistent night to night (but still varies if your room temp varies). It uses this data to pretty good effect for fertility and cycle planning for women and also to alert to POSSIBLE fevers. It's surprisingly accurate for these two things on other devices and I imagine it will be for Apple too. I suspect since many don't wear their Apple Watch to bed that Apple has tried to make this all work with many measurements taken throughout the day which makes the whole thing more difficult but I'm sure they have all kinds of machine learning and algorithms that will make it possible.

Apple pushed Cardio Fitness which is equated to VO2 Max, and hilariously inaccurate... they can push something that's not exactly internal temperature and call it something else.

 

[ProfessionalFan]

I would prefer that they focus on extending battery life to days/weeks, rather than introduce features that are poof limited application.

I would prefer they do both things at the same time.

 

[MacAddict1978]

This isn't new tech folks. Garmin, Fitbit, Whoop, and others have had it for years. You can NOT determine internal body temp from skin temp, there are too many variables... temp of the room, temp when you are outdoors etc. which all affects the temp of your skin. What these devices usually do is measure skin temp AT NIGHT when you appear to be sleeping because that tends to be most consistent night to night (but still varies if your room temp varies). It uses this data to pretty good effect for fertility and cycle planning for women and also to alert to POSSIBLE fevers. It's surprisingly accurate for these two things on other devices and I imagine it will be for Apple too. I suspect since many don't wear their Apple Watch to bed that Apple has tried to make this all work with many measurements taken throughout the day which makes the whole thing more difficult but I'm sure they have all kinds of machine learning and algorithms that will make it possible.

Words matter, and "can NOT determine" is not correct. You CAN measure body temp from skin.... you CANNOT guarantee its accuracy.

In the 80's these forehead strips were all the rage, quick, easy to ready... not under the tongue or in the bum. Still on the market today just rarely used. The problem is, a few degrees variance is the difference between having a fever and not a having a fever. (1.4 - 2.4 degrees in most cases.)

These sensors are essentially a digitalized version of these strips which can fluctuate +/- 5 degrees.

This is where an algorithm could solve for the variance by creating a baseline against the actual temperature of the air over a duration.

So yes, you can do this. Strips had an accuracy of 35-50% depending on brand. If a strip measures you are 102, you most likely do have a fever though probably lower. If they measure you are 97 you're probably more likely right around normal. Software could calculate averages based upon multiple readings and air temp and get a more accurate calculation.

Will it ever be as as spot on as rectal? Nope. But even mouth and ear scanners have a variance in accuracy without the ability to calculate multiple flash readings.

 

[mannyvel]

If the watch can't do temperature it can't do basal temperature, which generally speaking should measure .5 of a degree F difference or less.

 

[whidbeyben]

Body temperature sensing is a no brainer with the AirPods. A dirt cheap IR sensor can nab tympanic membrane temperature or even just ear canal readings very easily. You just need to connect them to the watch or iPhone through software via existing wireless connections. It nuts to think you can get accurate core body temperatures from a wrist worn sensor.

 

[CmdrLaForge]

I will get a new watch once I can use the cellular version with a budget carrier. Not sure who prevents this.