How does the iPhone count steps, and how accurate is it?

Every iPhone is a step counter. You don’t need to install anything or wear a watch: Apple’s Health app “automatically counts your steps, walking, and running distances”. The catch is in the word “phone”. It counts the steps it is carried for, and none of the ones it isn’t.

Where to see your steps

Open the Health app. Steps usually sit in the Pinned list on the Summary tab, which shows how you are doing in each category that day. Tap Steps for the day, week, month and year views. If Steps isn’t pinned, tap Browse, then Activity, then Steps, and pin it from there.

How accurate is it?

Accurate enough to track your own walking, with two limits worth knowing.

While it is in your pocket, the count is close. A 2015 study in JAMA had people walk on a treadmill at 3 mph (4.8 km/h) with an iPhone in one trouser pocket and an Android phone in the other, and compared the phones’ step-counting apps with the steps actually taken. The apps came within about 6.7% under to 6.2% over.

Over a whole day, it misses steps. A 2019 study compared each person’s iPhone with a research pedometer they wore at the same time. Across ordinary days, the iPhones recorded about 12% fewer steps on average: 9,253 a day against 10,530. The two still moved together well, so a day that looked busier on one usually looked busier on the other. The gap was larger for people who seldom carried their phones, and for people who usually carried them in a bag rather than a pocket.

In short: the iPhone counts well, it just can’t count steps it doesn’t go on. Steps around the house, at work with the phone on the desk, or on a treadmill with the phone in the cup holder are the ones it misses.

How to get a fuller count

• Keep it on you. A pocket beats a bag, and a bag beats a desk.
• Wear something on your wrist or finger, if you want every step. A watch, band or ring counts whether your phone is with you or not, and most can send their steps to Apple Health.
• Pick which count wins. If a watch and your iPhone both record the same walk, Health shows the count from the source at the top of its list, never both added together. To change the order, go to Steps → Data Sources & Access → Edit and drag a source up or down.

Walking with a finish line

The hard part of walking more is not the walking. It is having a reason to go out today. reTrek gives your walks a finish line: pick a famous route, like the Camino de Santiago or the Inca Trail, and every walk moves you further along it, with a short film about the place waiting at each milestone. Instead of fitting in a walk for its own sake, you walk to reach the next milestone.

Everest Base Camp is free. Get reTrek.