, conducted by the University of Toronto, concluded popular pedometer apps Runtastic, Moves and Accupedo are all unfit for use in medical interventions. The apps were compared to a $33 standalone pedometer which was found to be more accurate by plus or minus 5 percent in each case, outperforming the "smart" technology.
The simplest test involved the
apps being used to record people walking 20 steps at a regular speed. The pedometer was found to correctly record the number of steps traveled but the apps were less successful. Runtastic over-reported by 10 percent, Accupedo under-reported by around 25 percent and Moves under-reported by 30 percent. The apps only beat the pedometer when being used to record walking up stairs.
The study's authors concluded
there was an "unacceptable error percentage in all of the applications when compared to the pedometer." According to the report
, "the applications were neither valid nor consistent in the sample population under both controlled lab test and free-living conditions."
Smartphone apps are inaccurate because they rely on the accelerometer buried in the phone's hardware to work out when a user is walking. The phone may not fit correctly into the user's pocket, or could slip around when moving, adding a degree of error when measuring steps walked.
The input from GPS signals can also confuse the device. In one test, the researchers found that the apps would log steps while sitting in a slow-moving car because they interpreted the GPS motion as walking.
People who want an easy way to stay fit may turn to a smart band or fitness tracker but another recent study concluded these are even more inaccurate. The bands made by popular manufacturers such as Fitbit can add a degree
of error of up to 22.7 percent, compared with an average of 6.7 percent for most smartphone apps.
Fitbit is currently facing a class action lawsuit in the U.S. which is also based around inaccurate tracking. The claimants allege that the
heart rate data provided by Fitbit heartrate sensors is misleading and "dangerously inaccurate." A person using a Fitbit while working out may assume their heart rate is lower than it really is and begin another exercise, potentially damaging
their body on the advice of their trusted device.
With integrated smartphone apps and dedicated fitness trackers now both under scrutiny for inaccurate reporting, a newcomer to the space may be best advised to buy a traditional standalone pedometer instead. The University of Toronto described the
$30 pedometer's results as "pretty much bang-on" and "probably the most reliable and cost-effective tool for self-tracking your steps."