Google is gearing up to swallow a bigger slice of the small business pie, according to a recent TechCrunch article. The search engine behemoth plans to deploy 8 million custom mobile devices for small businesses in the U.S. The article states that these devices will let customers check-in and rate business and perhaps even purchase items via Google Checkout.

TechCrunch’s Michael Arrington reports that some aspects of the plan are still up in the air. For example, the thinking is that Google intends to give these first devices away for free, but there’s no word on whether the company plans to charge once the produce is more established.

The move could help Google compete head-to-head with wildly popular services like Facebook, Yelp and Foursquare – online to offline commercial efforts that comprise a large percentage of overall spending. The location-based social networking site Foursquare launched in 2009 with limited availability in only 100 worldwide metro areas. As of March 2010, Foursquare boasted 500,000 users internationally.

Yelp, a social networking, user review and local search site, lays claim to more than 31 million monthly unique visitors. And then there’s Groupon which offers one deal a day in cities around the world, granting local businesses a platform to advertise to millions of potentially new customers. That’s a scary proposition to Google as sites like Groupon convince small businesses that they can get more bang for their buck through Groupon coupons than if they purchased search ads through Google.

Of course, this isn’t the first time Google has tried to establish a toehold in a lucrative market dominated by Yelp, Facebook and Foursquare. Earlier this year, Jeremy Stoppleman, the CEO of Yelp, walked away from a rumored deal to be acquired by Google for more than half a billion dollars. A few weeks later, Google launched ‘Near Me Now,’ a mobile search tool that lets users search what’s around them at any moment without the use of search terms.