Surprise: the Ionic doesn't use GPS to measure distance. It uses stride length.
In the app's Account section, look to the bottom for 'Advanced Settings'.
At the bottom of that look for 'Stride Length'. There's a setting for walking and for running.
There's also a switch for automatic calculation. I have mine turned on... Ionic is supposed to periodically recalculate stride using GPS. I'm not sure how often it does this, when it does it and how accurate it is.
The initial estimate of stride length is derived from your personal stats; mainly your height. Make sure all your personal settings are correct.
If you prefer, you can measure stride yourself and manually update the app. Look for advice regarding how to do this (walk a set distance whilst counting your steps - then do the appropriate arithmetic and update your stride length setting.)
Before you become too incredulous that ionic doesn't use the accurate GPS data to measure distance and pace be aware that this displeases all of us - especially competitive runners that stategically seek to modulate their pace on race-day. We're all hoping Fitbit can improve their algorithms and improve this for us.
-bmw54
