Will the Apple Watch’s Coolest Feature Work for People of Color?

Alexis C. Madrigal, Fusion, March 9, 2015

On the back of the new Apple Watch, there are two sets of lights and sensors. One sends out and receives visible light, while the other works in the infrared part of the spectrum. Together, they form the technical core of the watch’s coolest feature–a heart rate monitor.

This kind of design–using optical sensors to measure pulse–is not unprecedented, but Apple, of course, claims to have improved the system over competitors like the Basis Peak, Samsung Gear Fit, or Mio’s line of activity monitors. Which would be a good thing, because these systems have struggled with their accuracy.


And because of the technology that most smart watch makers, including Apple, have chosen, the problems may be exacerbated if you have darker skin.


The technology is based on a laboratory technique called photoplethysmography, which uses a “pulse oximeter” to measure the components of the blood. A light pulse is sent through the skin and picked up by a sensor. Based on how the light scatters, the sensor can measure how oxygenated the blood is, which allows one to calculate heart-rate based on how often fresh, arterial blood is pumping through.

In the medical context, this oxygen level tends to be measured by a little finger cuff. So the light is on one side of the finger and the sensor is on the other. Even in this more controlled setting, there have been conflicting scientific reports about whether skin color impacts the accuracy of readings.

But no one wants to wear a finger cuff around while they work out, so fitness band companies have had to make do with the wrist. Even a flashlight can shine easily through one’s fingers, which makes the sensing task easier. A wrist-mounted sensor has to rely on the light that’s reflected back from the blood, not shining through it. That’s harder.

The skin on the back of the wrist tends to be darker, too, especially for people with more melanin. “The light has to penetrate through several layers…and so the higher the person is on the Fitzpatrick scale (a measure of skin tone), the more difficult it is for light to bounce back,”explained Basis COO Bharat Vasan to CNET.

Basis, and presumably Apple, try to compensate for skin tone by shining brighter light when someone’s complexion is darker.


Using optical technology to measure heart rate might also mean that people with darker skin will experience a greater drain on their watch battery, because of the more intense light required to power the sensor. The light required to do accurate measurements was enough to push Apple-competitor Jawbone away from an optical system to an electrical one: “Because bioimpedance requires significantly less power compared to optical sensors for same level of accuracy, we can deliver a smaller form factor and longer battery life,” they claim.


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  • Who wants a watch whose battery needs daily charging?

    Now that the Dick Tracy watch is a reality, the whole letdown of the matter is that I don’t want one, even though I could get a Moto 360 which works with my phone. The irony is that the smartwatches are basically BT accessories for one’s phone, but because of my phone, I no longer wear a watch.

    • bv

      People hardly interact act with each other these days, I don’t need any more distractions.

  • MrBiIIGoode .

    Garden variety negro – “Dat be racist white man tricknology”

    • Anna Tree

      If things continues the way they do, one day any technology/medicine etc that only applies or helps whites will be indeed branded racist and therefore not allowed to be researched and conducted…

      But of course, technology like the one revealing change of skin color in this video:
      ted com/talks/michael_rubinstein_see_invisible_motion_hear_silent_sounds_cool_creepy_we_can_t_decide
      will be continued if it is, if I foresee right, to find if a white person is lying.

  • Tim_in_Indiana

    One would think, judging from Apple’s ads, that blacks are the majority of Apple’s customers. However, since the Apple Watch decidedly falls into the category of “bling,” I suspect it will be quite popular with blacks. Therefore, the story of it not working with dark skin is nothing short of scandalous!

    • bv

      Can’t blame apple the blacks seem willing to waste their cash on any fancy gadget they can get their hands on.

      I remarked to one at work that I had a MacBook and I enjoyed it. Mine was about 3 years old at the time, that dude went out and bought the most expensive MacBook he could find.

      It seemed like he was trying to prove to me that he can afford it and subconsciously was seeking my approval or acknowledgement. It wasn’t a sense of trying to one up me, but of saying to me “I can do that too”.

      He would laud over & humiliate his fellow blacks each and every time.

  • TruthBeTold

    Apple clearly doesn’t care about the health of black people.

    • Samuel Hathaway

      With high incidences of promiscuous sex and its attendant diseases, drug use, over-eating all kinds of garbage like chitlins, fast food, vending machine candy, sugary sodas…i’d have to say they don’t care about their own health.

      • ozamataz

        Many of them seem to also fall victim to too much lead in their system.

        • John Smith

          Not nearly enough.

      • Alucard_the_last

        Which is somehow, our fault.

    • Light from the East

      Because that only tells them they got “problems”.

  • RacialRay

    Funny, I would have thought that with the ridiculously thin skin of most negroids in today’s pc wasteland, the devices would have no problem penetrating to the dark meat.

    Must be racis’ somehow. I’m gonna start a rumor over on World Star Hip-Hop that its not a heart rate monitor at all, but a new form of criminal ankle bracelet. Apple is tricking the brothas into rattin’ on dey own a$$.

    • Fathercoughlin

      The darker the berry the sweeter the juice?

      • bv

        How do you explain tropical fruit? The darker it gets, the more rotten & bitter the taste.

        Aren’t blacks from tropical climates?

    • Cujo

      Yeah…spread that rumor…maybe there will be fewer Apple iWatch thefts than there are Apple iPhone thefts!?!

    • HE2

      I dare you! Do it, racial. Do it.

    • bv

      Say the new smart watches are virtual slave chains and will force them to pick cotton at a later date.

  • Reverend Bacon

    Another “disparate impact” of Apple technology is that Siri doesn’t understand Ebonics. That racist harlot!

  • Fed Up

    In a word: Who cares?

  • MekongDelta69

    Blah, blah, blah, yadda, yadda, yadda = Translates to, Apple is racist

  • Samuel Hathaway

    Blacks get all the easy roles. They think they’re high-rolling techies for playing in a company skit.

    It’s the white brains and ingenuity behind the high-tech gadgets that provide all the “diversity initiative” jobs and the spots in the ads. But that’s a white thing. Blacks wouldn’t understand.

    • Operating a sailfoam is high tech for a bantu.

      • Samuel Hathaway

        Sailfoam? Oh, I got it, CELLPHONE. Yes, I thought at first glance you wrote “sailboat”….LOL…

        Some blacks I come in contact with playing on these “sailfoams” with all the bells and whistles, I ask how much they pay monthly for that stuff… some say as much as $200/mo. but usually the average is around $100. As for myself, I still have the “flip phone”: with 400 weekday minutes, M-F and 1000 night/weekend minutes. All for $29/mo. All told, my cellphone bill is slightly less than $1 per day.

        One thing I’ve learned that blacks insist on the latest, greatest, neatest gadget out there, and don’t consider the extravagant cost, and putting some of that $$$ away to grow in some kind of acct.

        • As much as I like (and can now afford) today’s smart phones, I still have a basic, inexpensive cell phone; not quite ready to pull the trigger.

          • ghettovalley

            Some decent prepaid android phones can be purchased for less than one hundred dollars. I have been using this phone every day for two years, and I paid only sixty dollars for it, on sale. It doesn’t look cheap or old at all. My plan is only thirty to forty dollars per month with no contract.

  • A Freespeechzone

    Poor, uneducated minorities are NOT the target of Apple for customers; only educated, working who can afford their products are the focus of Apple.

    THAT is what Obama phones are for…..the poor, stupid and lazy–at the cost of the taxpayer.

  • Fathercoughlin

    It would be funny if the whitey at 0:02 looks at the negro and recognizes…that he is wanted for rape. I guess that wouldn’t fit the spirit of the ad tho.

  • Fathercoughlin

    “(The darker the skin) the more difficult it is for the light to bounce back.” This puts me in mind of the Blues Brothers: “…a rubber biscuit is the kind of a biscuit that’s suppose to bounce back off the wall and into yo mouff!?If it don’t bounce back—hmm hmm hmm hmm hmm–you go HUNGRY!!”

  • Fathercoughlin

    At 0:16 one Anthony Frasier. Doesn’t this guy look like somebody who’d get shot trying to kill a cop??

  • The comedic fiction – along with negro-worship – gave me douche chills.

  • Cujo

    Great…so now you’re telling me watches are racist? Sheesh…what next?

  • InAFreeCountry

    “The skin on the back of the wrist tends to be darker, too, especially for people with more melanin.”

    That’s odd, mine is noticeably whiter, from wearing a watch and getting less sun there.

  • LeonNJ

    Wasn’t there some camera thing some years ago that was supposed to follow your face on webcam, but it had a hard time with black and Asian faces?….damn whites and their technology!

    • John Smith

      Blacks are exactly the ones that need to be recognized and profiled against a database.

  • John Smith

    Apple is racist.