One of the unique features of Sail is the test facility that allows you to define a route, walk along it, and measure positioning accuracy. (This feature is only available when using Sail built-in mapping, not when using imported floorplans from other mapping providers.)

The accuracy figure that is generated is the root mean square error (RMSE) of the positions generated along your walk.

Accuracy varies depending on the phone, the beacon density and layout, and the environment. The best accuracy achieved is usually between 2m to 3m RMSE. But lower accuracy is often still sufficient for many use cases.

At the end of each walk, the RMSE is displayed, along with a description to help you interpret the measurement.

RMSE below 4.2m will typically provide a good navigation experience and is very valuable for analytics and location-based personalisation.

RMSE from 4.2m to 6.5m  will usually be adequate for navigation and other use cases. But improvements may be possible.

RMSE from 6.5m to 10m can often be improved. But will still be of value for many use cases

RMSE greater than 10m can usually be improved. But can still be of value, particularly for larger sites.

If accuracy needs to be improved, the first step will be to look at the beacon installation. You can use the coverage map feature in the Sail console, as well as noting the areas in which test walks performed poorly.

Installing additional beacons in the required areas will normally improve accuracy to the required level.