Anyone relying on customer reviews to gauge the accuracy of iPhone step counter apps is likely to stay confused.

With user comments ranging from “surprisingly accurate” to “way out” (in terms of steps taken/distance covered), how are we to sift something useful from the mass of conflicting information?

One way is to ask yourself why you want it in the first place. If you want accurate measurement of distance, then the iPhone counter is not the best tool for you. One tester, when comparing it over a known distance with a vehicle odometer and a pedometer, reported that the iPhone app didn’t come close to the accuracy of the others.

Obviously, it helps to know your stride length (even my old-fashioned pedometer required to me to take 20 steps and measure the distance in order to get a realistic average), but stride length can change, depending on the nature of the terrain over which you are walking. In any case, if accurate distance measurement is your main requirement, then a GPS watch or GPS app will give you a far better result.

A TV test of 30 joggers using various step counters found them all to be inaccurate, both in terms of distance covered and the number of steps taken.

However, not everyone is concerned with exactly ‘how far?’ or ‘how many?’. Many merely want to know whether they are working as hard or harder today than yesterday. In this instance, iPhone step counters can prove a useful tool, provided certain pit-falls are avoided.

An iPhone cushioned in a bag or rucksack, for example, is likely to give a false reading, as is one subjected to excessive shaking or vibration. The general consensus is that these devices are consistent with themselves, provided they are used carefully. Hence, the key is consistency. Wear it/use it in the same way each time and your iPhone should give you a good indication of comparative workload, even if the numbers are not absolutely accurate.

For a wider discussion of the subject, check out the following link: