Pedometer Apps and Accuracy

michikade

I just did a little experiment today.

I use Moves and Argus (both for iPhone 5), which both have pedometers that run in the background. I've always known there were discrepancies, but this was a little... disheartening.

Both apps ran all day. Battery remained charged and phone remained on.

At the end of the day (it's 11:35pm as I type this), I'm seeing these results:

Moves: 10,245 steps, 4.6 miles, 2h 7m active.
Argus: 13,013 steps, 5.36 miles, 1 h 55m active.

My Fitbit Zip battery is dead at the moment, which is why I'm using these apps at the moment anyway, so I don't have a 'true' pedometer to compare to these results (although I've found my Fitbit tends to be under most of the time). The walking I did today was all from shopping and running errands.

My question is: has anyone run into similar issues, and does anyone know which one of the two apps is more accurate? Neither sync with MFP so that's not a factor, although Moves DOES sync with, like, everything (including Pact, woo!) but if it's ridiculously inaccurate then it may not be worth it.