Geolocation in the Browser

Geolocation is arguably one of the most powerful capabilities of smartphones and a lot of attention has been paid to native applications that make use of it. The discontinued Google Gears plugin was one of the first approaches to access exact location data on the Web as well, apart from server-side coarse location lookups based on Internet Protocol (ip) addresses; and the plugin led directly to the now widely implemented Geolocation api. The World Wide Web Consortium (w3c) Geolocation api specification defines a standard for accessing location services in the browser via JavaScript. For a long time, developers have also demanded more advanced features like background geolocation tracking and geofencing. The w3c Geolocation and the Devices and Sensors Working Groups, as well as the Web Incubator Community Group (wicg), have addressed these demands with the no longer maintained Geofencing api specification for the former, and—with now (early 2019) resumed efforts—the in-flight Geolocation Sensors specification for the latter two groups. This paper first provides an in-depth overview of the historical development of geolocation in the browser and motivates privacy decisions that were made at the time, and then gives an outlook on current and future efforts, challenges, and use cases from both a technology as well as from a privacy angle.