How accurate is the step counter in the health app on the iPhone

I also think it may be very dependent on clothing. I often walk the same path with my wife, mostly level, of just under 4 miles per GPS. Her FitBit on her wrist is very consistent. My iPhone will register sometimes double the actual distance (and number of steps), and sometimes be fairly close. It always counts more steps than her FitBit, even though she is considerably shorter and has a shorter stride. The iPhone is nowhere near consistent with itself. I have the iPhone in my pants pocket, and I have suspected that bouncing is causing it to count more steps. It's kind of a running joke between us- about how many steps I got today. Back pocket seems more accurate than a pocket on cargo pants/ shorts. When she tried her iPhone on an arm mount it was fairly close to her FitBit.

I've had reason to test a large number of activity trackers, GPS watches and similar devices. For running out of doors, I use a GPS watch. As it happens, the one I have also has a feature where, with the correct heart rate strap, it will also figure distance on treadmills. It's able to do a neat trick where it calibrates that step tracking using the GPS data while you're outside. That means when you come in and run inside, it's quite accurate. I don't think I've found an activity tracker that does that yet. Or that states explicitly that it does. Seems like something Apple out to be able to do.....

Best of luck.

All good points from everyone here, I suppose given the high tech world we live in, I was expecting just a little more accuracy than seems reasonable. It would seem a good ideal to be able to enter ones stride, than does not seem like it would be to tough to write that code, maybe in a future update. You know the difference in a 4 foot 10 female and 6 foot Six male, would be quite different. But thanks to everyone for your input, I always come here for good ideals....Take care All!

I noticed a peculiar thing. The number of steps and the distance depend on the pants I am wearing. I walk a carefully measured distance of .33 miles verified by my car odometer average of 5 circuits and by my hand held GPS. When I wear jeans the iPhone is accurate within .01 miles in 2 miles. When I wear shorts the iPhone is over by varying amounts sometimes almost double. I have tried this several times and the results are consistent (in the sense that the shorts are always significantly more). The jeans distances are very consistent from trip to trip. The shorts are not consistent with either the jeans or themselves. I think the reason is that when I wear jeans they are tight enough to keep the iPhone on the front of my upper thigh. The shorts have a pocket more like dress pants and the iPhone sort of swings back and forth in the pocket beside my thigh. I think it “rebounds” at the back of the swing and counts more steps then there are. I would be very interested if anyone else has experienced this.

So far I cannot see that it is even close, when measuring the same distance with a pedometer or odometer on my truck! Thats steps or miles. If someone has a suggestion that I may have missed, I'd love to hear it. I can't see buying the apple watch for fitness if it is that far off. I'm

talking the IPhone 6 is telling me I am walking nearly double the steps that the pedometer says and I know the pedometer is correct as you must measure your stride with a tape measure and enter that figure into it......

I hate to slice this conversation too thin, but it does matter if what you want is close approximation of the # of step you are taking. If you need to log 15K step a day, consistency means little to you. In psychometric terms, validity (measures what the scale purports to measure= steps) is more important than reliability (consistency over time), but if your scale is not reliable, it's meaningless. Make sense? And I'm still looking for a well designed measurement study of the Apple Health app with FitBit, which are miles (OK, steps) apart. I read somewhere that suggested that one can enter your stride which would help, but so far that appears to pertain only to the Apple Watch.

-js

andycaprichardson wrote:

I know that mine is way less than measured, apple please fix this, it was the main reason I bought it!

Apple is not here. If you want to send them feedback, use this page:

http://www.apple.com/feedback

If you think there is a problem with your device, make an appointment at the Genius Bar at your local Apple Store.

Again, for general fitness purposes, what matters is not the absolute accuracy but rather that it is consistent with itself, that every time is says "one mile", the same distance has been measured. The goal is to keep increasing your activity. The actual distance, unless you're training for a specific race distance, is far less important.

I am prepared to accept that nobody walks with equal length paces on any type of surface, and movements other than actual steps will add to the count, and actual steps will be missed. I believe that any pedometer reading, be it a plastic thing on your belt or the latest iPhone, should be seen as a rough guide only. If you want to know exactly how far you have walked run or driven, there are plenty of GPS apps that will give you an accurate result.

magnum12pm wrote:

I can't see buying the apple watch for fitness if it is that far off.

For general fitness, it doesn't matter if it's accurate to the exact number of steps you've taken. What matters is that it's consistent. If it counts seven steps for every five you take but it always does that, you'll know if you're taking more steps over time. And that's generally the point of activity trackers.

As tonefox suggests, if you need accurate distance, say, if you're trying to qualify for Boston, get a proper running watch with GPS.

Shatz wrote:

I hate to slice this conversation too thin, but it does matter if what you want is close approximation of the # of step you are taking. If you need to log 15K step a day, consistency means little to you. In psychometric terms, validity (measures what the scale purports to measure= steps) is more important than reliability (consistency over time), but if your scale is not reliable, it's meaningless. Make sense?

I disagree. As long as the measurement is consistent (the tracker always records 5 steps for every 6 you take), that's valid. My experience with a number of different trackers is that they are consistent to themselves. Therefore, they serve the purpose of telling you that you are increasing or decreasing your activity level which is what is important. Arbitrary numbers such as 10,000 or 15,000 steps a day are just that, arbitrary numbers. They have no particular scientific meaning. The idea that 10,000 steps should be a goal is based on the fact that "10,000 steps" sounds good in Japanese so the company that marketed one of the first popular consumer pedometers used it as a marketing gimmick.

From a health standpoint, what matters is that you are active. For most of us, that means increasing our activity levels.

I Just did several tests for accuracy. First I took 100 steps with the phone in my cargo pocket and it counted 129. Then I took 100 steps with the phone in my side pocket and it said 108. Then I took 100 steps with the phone in my jacket pocket and it said 98.

Then I took the advice to enter my height and weight into the health data. And I did the same three tests. Now the results were: Cargo pocket: 139 steps. Side pocket: 107 steps. Jacket pocket: 102 steps.

Looks like the jacket pocket wins hands down. For the record it's a side pocket on my jacket.

Its been more then a year I am using Health apps actively for Steps counts, Heart rate, and other health info on my iPhone 5S.

I frequently go for trekking, with my friends having iPhone 6S.

Every time I found there is huge difference in steps counts in different phones.

Being an iOS Developer I started digging inside to understand how it works.

Basically it uses iPhone motion sensor Class name "CMPedometer"

so whenever device get motion steps counts get started. it doesn't matter with GPS.

so even your not running/walking, just sitting on chair but you moving your device in 10-20 inch area, boom!! there you will get after few seconds steps counted get updating.

I have sent my feedback to apple developer guys regarding this. even there was trekking day i walked around 52-55 km. but application showed only 28Km and steps counts were 7453.

- - - - - - - - --

"so its the motion not time or GPS which matters here"

The app is just not accurate at all. I put my phone and my wife's in my pocket and took a long stroll around

the mall. My steps measured 4460 - 1.9 miles. My wife's phone measured 3762 steps - 1.3 miles. Now both of the phones were in my pocket. I'd say this step counter is not very trustworthy and basically useless.

joepforge wrote:

The app is just not accurate at all. I put my phone and my wife's in my pocket and took a long stroll around the mall. My steps measured 4460 - 1.9 miles. My wife's phone measured 3762 steps - 1.3 miles. Now both of the phones were in my pocket. I'd say this step counter is not very trustworthy and basically useless.

For purposes of general health, it doesn't really matter if the distance is accurate. What matters is that it's consistent. For example, if the watch always measures 1.3 miles as 1.9, you'll still know if you're getting more or less exercise than you were the day before. For general health, the important thing is to become active and stay active. There is no magic number of steps.

If you look at what the Watch focuses on, it's not steps or distance. It's minutes of activity and exercise. Activity is a combination of movement and heart rate.

If you're training for a marathon, the Watch is not your best option. If you want to improve your activity levels, it's very useful.

I have seen if you changing your height will change the step length.

Not much of a-work-around, but it works

You can leave them feedback

http://www.apple.com/feedback/iphone.html