Using a Measuring App

Most smartphones are equipped with a measuring app, or the ability to download one for free.  This is an additional layer in measurement accuracy and discreetness in the store.

iPhone users: Measure app

The Measure app comes standard on Apple platforms, usually grouped in the "Utilities" category. You're able to choose a starting point, and drag the line to the end point point to get the linear distance measurement.  

Android/Google users: Smart Measure

Smart Measure is a free download for Android/Google platforms.  You're able to dictate a starting point, and drag to an end point to get a linear inch measurement.

Any device: Map My Walk

This app comes as a free download on all platforms. After turning on location services for the app, you're able to track footsteps and distance.