Opera becomes the latest browser platform to support location awareness through support for a draft of the W3C geolocation API. The group joins Google (via Gears) and Mozilla (via a future Firefox release) in letting a browser, with permission, tell a web application where you are.
Putting location in the hands of a website or web application makes sense for a variety of activities: finding your location without knowing where you are is an obvious one, as is navigation. However, location is commonly used on mobile devices to tag photos, point you out to your friends in social networks, and play real-world overlay games.
The geolocation API functions (but isn't implemented) in a similar fashion to the iPhone's Core Location service. iPhone developers can use Core Location to obtain coordinates, which are derived on the iPhone 3G from a combination of WiFi positioning, cell-tower trilateration, and onboard GPS. iPhone users are always asked before an application obtains location the first time whether or not that's acceptable.
There's currently an active debate in the W3C geolocation drafting group as to whether the API should include specific privacy provisions, or whether that should be extra-specification and bumped up to the browser's maker to determine how permission and privacy is handled.
Opera's first pass at geolocation, in a beta build, is paired with Skyhook Wireless's WiFi positioning system. Skyhook is used by Apple as a primary method on first-generation iPhones and part of the location system on iPhone 3G models. The company constantly drives cities around the globe to update WiFi scans, and also integrates snapshots sent every time a phone or laptop requests location data based on its WiFi environment.
Google's Gears Geolocation API was announced October 2008, and it relies on a Google proprietary WiFi location server that the company won't provide details about.
The Mozilla Foundation has plans to have full geolocation support in Firefox 3.5, but enabled it in a beta of 3.1 to provide early exposure to developers. The group plans on allowing multiple location information sources, although as of the last discussion in a developer blog in Octoboer 2008, no decisions had been made about what kind of location provider support would appear in 3.1.
Source: ars technica