MOUNTAIN VIEW, California: Google, the online search giant, has scrapped its radio advertising system Audio Ads, which aimed to increase the measurement options for marketers using the medium. Microsoft, on the other hand, has announced it is to open a chain of retail stores.

Launched three years ago, Google's Audio Ads had been backed by the purchase of radio advertising technology firm dMarc in 2006, the total cost of which could have reached $1.24bn (€966m; £855m) had the system proved a success.

The decision follows on from its decision last month to shut down its Print Ads service for newspapers.

Clear Channel, America's biggest radio broadcast group, had trialled the Audio Ads service, and a spokesman for the company said it was “disappointed that Google is ending the program."

By contrast, Microsoft is aiming to expand its operations into retail, and open a “small number” of stores, a move some observers argue is an effort to take on one of its major rivals, Apple.

The company has appointed David Porter, who has held high-profile positions at both Wal-Mart and DreamWorks, as its corporate vice president of retail stores, with responsibility for identifying where and when the new stores should be opened.

Data sourced from Wall Street Journal/New York Times; additional content by WARC staff