Its acquisition offers spurned by both local reviews site Yelp and geo-commerce startup Groupon, Google remains committed to strengthening its socially-oriented, location-based services for mobile devices, even if that means duplicating what it has been unable to buy.

On Wednesday, the company released Google Places for iPhone, an app that provides access to reviews of nearby businesses and allows users to submit such reviews. The Google Places app incorporates Hotpot, which WiFi-starved mobile users might misread as "hotspot" but is actually a local recommendation engine and social networking play.

Hotpot shares and surfaces reviews and tips submitted to Google Places among friends -- as determined by Google's awareness of one's social graph -- to give users a sense of what their friends think about various places.

The problem Google faces is that it doesn't know a lot about its users' friends, certainly not as much as Facebook. To address this problem, the company has made the Hotpot review process extremely easy.

And Google is encouraging users to sign in to Hotpot on a computer -- where data entry is easier than it is on a mobile phone -- in order to submit a list of friends. By urging users to write reviews (without compensation) and to identify their friends, Google is hoping a social network will emerge.

"Once you've added friends, you’ll find your results seasoned not just with reviews from around the Web and recommendations based on your own personal taste, but also with your friends' opinions too," said Google engineer Greg Blevins in a blog post.

If enough people do that, Google too will become a social network.