Providing a web-based service featuring technology that enables operators of brick-and-mortar retail establishments to detect, analyze, and act upon the location of mobile devices within such retail establishments; Providing a website featuring non-downloadable software for using the location of mobile devices within brick-and-mortar retail establishments to create targeted or personalized communications, and to deliver, monitor, optimize, and analyze such communications; Providing a website featuring non-downloadable software for the set-up and monitoring of electric or electronic sensors and proximity sensors; consulting services in the field of deployment, programming, and use of electronic sensors or proximity sensors for location of mobile devices; consulting services in the field of non-downloadable software for creating targeted or personalized communications using location data of mobile devices, and for delivering, monitoring, optimizing, and analyzing such communications