The 10 most likely sensors in a 10-sensor Apple smartwatch

“Ten sensors sure sounds like a lot of hardware to stuff into a smartwatch. Yet this is just the baseline sensor count that’s purported for Apple’s yet-to-be-announced iWatch,” Jon Phillips writes for TechHive. “The Wall Street Journal says Apple’s mythical smartwatch will actually have more than 10 sensors, leading me and other tech pundits to ask, How is Apple going to get past that magic number 10?”

“Once we begin looking at the current wearable hardware landscape, we see that 10 or more sensors might sound like an indulgence, but none of the sensors Apple might include is particularly esoteric,” Phillips writes. “An expert tells me that a blood-glucose monitor is off the table (more about that below), but a suite of much more pedestrian sensors are available today, and could appear in an Apple smartwatch — should Apple deign to release one.”

The 5 most likely sensor suspects:
1. Accelerometer
2. Gyroscope
3. Magnetometer
4. Barometric pressure sensor
5. Ambient temperature sensor

Sensor suspects 6 through 10:
6. Heart rate monitor
7. Oxymetry sensor
8. Skin conductance sensor
9. Skin temperature sensor
10. GPS

Each sensor discussed further, and why a blood-glucose monitor is a no-go, in the full article here.

[Thanks to MacDailyNews Readers “Fred Mertz” and “Dan K.” for the heads up.]

Related articles:
Apple’s iWatch could be the next big sports fashion accessory – June 21, 2014
Apple enlists MLB, NHL, and NBA pro athletes to test iWatch fitness capabilities – June 20, 2014
Kobe Bryant seen on Apple’s Campus reportedly meeting with Jony Ive about upcoming products – May 15, 2014
Apple’s iWatch awaits FDA approval; device to include blood glucose, sweat analysis sensors – June 20, 2014
Apple to begin mass production of 2.5-inch iWatch with wireless charging and pulse sensor in July, sources say – June 19, 2014
LG to supply Apple iWatch display in two sizes for late 2014 release, sources say – April 15, 2014
Apple’s iWatch said to come in two sizes, high-end model to cost several thousand dollars – April 10, 2014
Apple iWatch to sport 1.52-inch curved OLED, set for summer launch, report claims – January 20, 2014
Apple to make two iWatch models: 1.7-inch display for men, 1.3-inch for women, sources say – November 13, 2013


  1. iWatch. Yeah, I watch it fail if the above is what it is all about. Like Samsung failed. What the hell good is barometric pressure? How would you calibrate it, using GPS? Might as well use GPS elevation and forget ancient arts. Magnatometer? For finding coins in the sand? Or maybe studs in the wall. And temperature sensor? How is that going to work strapped to your warm wrist under your shirt inside your coat? And the accelerometer, for Olympic sprinters? I cannot imagine many folks would pay for those kind of measurements. Over the years I have had a variety of tools to measure such things, guess I will have to dig them out the drawer they have been in gathering dust.

    1. Instead of taking the time to carefully explain why you’re a shortsighted, visionless waste of oxygen, CJ, I’m just going to respond to your posts from now on with the one word that best describes you: Moron.

    2. I commented about barometric pressure after Cubert’s comment. Elevation is another one that’s easy to simply look up from existing measurements. Spot on.

      A ‘magnetormeter’ is merely a compass. They’re already present in many iOS devices. I seriously doubt an actual ‘meter’, or measuring device, would benefit anyone in a watch. It would have to have its own large magnetic reference inside itself in order to provide a relative reading. And of course, sticking a strong magnetic source inside a watch is a really bad idea for various reasons, from the practical to the woowoo.

      Accelerometer: That would have to be a very short term measurement and would be affected by momentum. The only real use we’d have for such a thing these days is similar to the use of a compass. It would measure ON or OFF, MOVING or STILL, in some relative direction. It would be like we have in a pedometer/Nike+ running app with an added direction component. And again, you’d have to calibrate it for each individual. Imagine the affect of swinging your arm! Kind of hard to use.

        1. Does it actually measure magnetic field strength? How sensitive is it? I have to assume it can’t be diverted from being a compass unless you’re rather close to a magnetic field source.

          I used to have a compass on top of one of my stereo speakers. I totally screwed it up over time. There’a a major magnetic field source! 😉

    1. Good point. Measuring barometric pressure would indeed be tough. You’d have to be able to calibrate the device, and it would take up some relatively substantial space with common materials. But there may be some possibilities.

      Considering the relative lack of importance of knowing barometric in any one exact spot at any time, I’d suspect Apple would instead provide a simple and fast readout app of local measurements in your geographic area. That’s easy and just as useful. I can already do that with a couple different weather apps for iOS.

      1. This would be highly useful to us in the outdoors community. In the mountains it IS useful to know that the barometric pressure is dropping at a point in time, as while passing a bailout point. I’m not saying this helps everyone but I would buy the watch for that feature.

        1. I see your point!

          So I looked around and found this interesting thing from 2009:


          EPCOS is introducing the most compact packaged sensors for barometric pressure measurement worldwide. With dimensions of only 1.7 x 1.7 x 0.9 mm³, the components are many times smaller than comparable competitor products and underscore EPCOS’ competence in innovative miniaturization solutions. The new pressure sensors open up numerous application perspectives for future generations of equipment and systems – above all for portable electronics. Portable navigation devices, watches and mobile phones, for example, will be able to measure air pressure and/or altitude above sea level.

          There we go! 😀

      2. I thought Barometric sensors detected humidity so if used on devices in close proximity to sources of moisture (e.g. skin) it would be rendered inaccurate. The ambient temperature sensor is the same, if near sources of heat/cooling (e.g. skin again or device itself in direct sunlight) the value would be rendered inaccurate. Both types of sensors are usually found in devices that try to eliminate those types of interference. (e.g. wall hung clocks and such)

    2. I offer this as a data point. I typically hike/walk/bike using the Cyclemeter app on my 5S. When I hike every week it’s typically a 3 hour, 5 mile loop over the ridge near my house.

      I use the GPS tracking and heartrate monitoring function of the app connected to a WahooBlue HR monitor (Bluetooth). I also have a Morphie Juicepack Plus battery pack on the 5S.

      Even during warm summer walks, the Juicepack has only one (out of 5) indicator lights remaining. In the winter (temps down to 10-degree range) the Morphie will discharge and use about 10-15% of the 5S battery.

      For optimal data recording, the 5S can’t be covered by bulky warm clothing.

      To make a long story short, I’m curious how an iWatch will have sufficient power to support all of these proposed options. I’m all for it and would most likely get one, but I want to see the power specs of this puppy, too!

  2. An expert tells me that a blood-glucose monitor is off the table

    Has someone been reading our discussion about it here at MDN? That would be funny. No, thank goodness:

    Ries Robinson told me in March…. Robinson is CEO of InLight Solutions, a company that develops sensor-based measurement systems for life-science applications…. “We’ve had some success—not to the accuracy needed for a medical device—but we’ve had some success in making optical measurements of glucose in the human body,” Robinson says. “The instrumentation we’ve historically used to make those measurements is approximately $10,000, and requires that you use wavelengths of light that are in the near infrared. But all of the wearable devices I’m aware of today use a silicon detector, and there isn’t any optical information in the silicon region for glucose. If there were, it would be terrific. You’d have non-invasive glucose meters for people with diabetes. But there’s no information.”

    NOTE that Jon Phillips who writes for TechHive left out blood pressure measurement. That’s another one that obviously can’t be measured accurately via a mere watch, especially at one’s bony wrist. But I’ll bet some daft company will try it anyway (hello SpamSprung).

    ∑ = Nice article! I like nice articles. 😀

  3. I find it hard to believe a gps will be in the watch. Not unless Apple has developed some kind of new super small and powerful battery. Just look how a gps drains a smartphone.. with a much larger battery!

  4. 10 most likely characteristics of a unicorn:

    1. Shaped like a pony
    2. Single twisty horn
    3. Fur made from pink cotton candy
    4. Silky, curly mane and tail
    5. Wears lip gloss
    6. Able to leap tall buildings and clouds
    7. Farts rainbows
    8. Hooves painted with sparkle polish
    9. Makes no vocal sounds
    10. Visible only to little girls age five and under

  5. Actually, the glucose sensor is possible. I, for one, am hoping Apple stuns all the naysayers with this. The stock will really take off. The FDA would need to approve it. That’s the key.

  6. Does anyone here knows how blood flow metre measures its data, how sensors and transducers respond to electrolyte…..etc……most people here dont even know how sensors and transducers work…and there have been advancements in the field of sensors beyond stuff mentioned here. Who knows what combination of electronics Apple would deploy in iWatch. Rest assured they would be functioning to highest level possible! And I as an OBSERVER have seen APPLE change the WORLD with their INNOVATIONS. You don’t need to look far into the past for proof. So PLEASE PEOPLE, MAKE BETTER ASSUMPTIONS AND SPECULATIONS otherwise we will look STUPID when iWatch is UNVAILED.

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