Is your iPhone step count accurate?
· 4 min read
Yes, for the steps it is there for. The iPhone counts walking accurately when it is in your pocket. What it cannot count is the walking you do while it sits on a desk, a kitchen counter or a charger, and in ordinary life that is most of the error.
What happened when people just lived with it
A 2019 study in JMIR mHealth and uHealth gave 54 adults a validated pedometer to wear on their waist for a week, alongside their own iPhones, used however they normally used them. The iPhone recorded 9,253 steps a day. The pedometer recorded 10,530. That is about 12% short, or roughly 1,300 steps a day.
The gap tracked how often people carried their phone. Those who said they almost always had it on them lost about 900 steps a day. Those who seldom did lost more than 3,000. The authors put it down to the time the phone was not being carried, not to bad counting.
The Apple Watch does better for the obvious reason
It is on your wrist. A 2018 study in the Journal of General Internal Medicine put 71 adults on a treadmill at four speeds, from a slow 1.9 mph walk to a 5.2 mph jog, and the watch landed within about 3% of the true count at every one. A treadmill is kinder than real life, but the watch never gets left on the counter, which is where the phone loses its steps.
Why the phone and the watch show different numbers
Both are counting, and both send their steps to Health. Health does not add them together. Apple’s own support page says that when several sources record the same kind of data, the one at the top of the list takes priority, and that new devices are added at the top, above your iPhone. So once you pair a watch, it is the watch’s count Health trusts wherever both of them were counting.
You can see and reorder that list: in Health, open Steps, then Data Sources & Access.
When it is not counting at all
A total stuck at zero is usually a permission rather than a broken phone. Go to Settings, then Privacy & Security, then Motion & Fitness, and check that fitness tracking is on and Health is allowed to use it.
What it means for the number in Humblebrag
Humblebrag reads Steps from Health, so it gets whichever count Health trusted. If your phone spends the afternoon on a desk, your comparisons run low, by 12% on average in that study, which for an app called Humblebrag is at least on brand. Carry the phone or wear the watch and the miles and calories follow.