The distance is consistently slightly off for my trainings

Equilab determines the distance continuously collecting GPS data from your mobile device while you're riding. It uses that GPS data to determine the distance of your training. Sometimes, the distances tracked will not perfectly match those stated on trail markers, maps, or other apps.

Such differences exist because raw locations that get reported from your phone's GPS often include some data points that are inaccurate (i.e., not on the path you actuallyrode). For this reason, Equilab (and other tracking apps) try to filter out these inaccurate data points before showing your final path. The specific algorithms used to determine which data points are filtered out and how much 'smoothing' occurs varies between the apps. Each app aims to make its tracking as accurate as possible, though they can sometimes vary by up to 15%.

Some of the primary contributing factors that explain why Equilab may vary from other apps include the following:

• How much time you spend standing still
• Whether you rode exclusively or partially indoors (Equilab tries to collect GPS data even when a roof is blocking the signal)
• How much 'smoothing' occurs to the path (Equilab aims for smoother paths than most other apps, which more accurately represents users). 

To the last point on this list regarding how 'smooth' your path is, a slightly more complex geometric problem called the coastline paradox is relevant. You can see an image illustrating the 'smoothing' on this webpage, by comparing the blue line (smoothed segment) to the orange line (raw data). 

Note that several other apps choose to provide distances that are longer than reality because it makes their users feel like they are travelling further and faster. Equilab avoids inflating such distances and aims to provide the most accurate estimate possible.

If you have any additional questions, please feel free to contact us at support@equilabapp.com. We're always here to help.