The Location Sensor is a Power Add On feature.
The location sensor feature is turned on/off with a simple check box under the General/User Interface tab.
When the box is checked and a visitor to your site performs a search , SLP queries the browser and requests their current location. If the browser allows location queries it will return their geographic location which will be used to set the default search location.
Note: This will only work if you have a secure site. Google and Chrome have had restrictions since Chrome version 50 (released in 2016) and they will only return locations using location sensor if the request is generated within the url of a valid site (https://). See the Google developers console for more information.
Location Aware Browsing
Accuracy varies greatly from location to location. In some places, our service providers may be able to provide a location to within a few meters. All locations returned by our service providers are estimates only and we do not guarantee the accuracy of the locations provided. Your SLP settings also determine the number of locations shown nearest the site visitor. Settings for radius, number of results to return and center of map all interact to show locations nearest to the site visitor.