While competitors such as eBay and Yahoo are making big splashes with acquisitions worth hundreds of millions, Google continues to buy much smaller companies with little media attention.

Those acquisitions nevertheless provide a hint of what Google is up to, observes the Washington Post. In the two years since going public, Google has purchased at least four startups that specialize in mobile software, which suggests that Google intends to bring search and other web-based services to mobile customers.

Google's apparent acquisition strategy is to purchase companies that augment and improve its existing strengths rather than expand into new areas, allowing it to develop and integrate these companies in-house. For example, Google has also purchased two companies focusing on online advertising and two search engines.

Google's familiarity with the sectors it targets could also explain why its competitors, such as Yahoo and eBay, have spent 3-4 times as much for their acquisitions.