Square hits the iPhone. Square, the start-up that lets small companies accept credit card payments using nothing but a cell phone and a little plastic doohickey, is now available on the iPhone or any Android handset. The start-up was co-founded by Jack Dorsey, the engineer who created Twitter and who initially served as its CEO. Fast Company breaks the news. It reports that Square is "both a foolproof and attractive experience" that will likely appeal to small merchants, political candidates canvasing for donations, or anyone selling their junk on Craigslist.

Please retweet! So your company has amassed a substantial following on Twitter. But are they really hanging on your every tweet? A new paper from the Max Planck Institute for Software Systems in Germany argues that the real measure of a company's influence on the social network is not its number of followers, but the number of times its messages are repeated--er, retweeted--according to GigaOM. So when you tweet, try to say something worth repeating. Inc.com has more ideas on how to make money on Twitter.

Chatroulette founder comes to America. This week, Andrey Ternovskiy, the eighteen year old Russian founder of the world's weirdest social networking website, Chatroulette, gets the New Yorker treatment. In Julia Ioffe's story, we learn that Ternovskiy struggled in school--his offenses included "chronic truancy and correcting the English of his English teacher" (he learned English by chatting with friends online). A few new details emerge about Ternovskiy company: Chatroulette attracted 48 million visitors over a 3 month period; it employs five programmers in Belarus; and it makes about $1,500 a day. That may seem modest, but, according to the article, it was enough to get the attention of Fred Wilson, the New York VC, who helped Ternovskiy get a tourist visa to come to the United States. Ternovskiy is now in Palo Alto and says he plans never to return to Moscow.

Meet the man behind those racy Super Bowl ads. The Baltimore Sun has an interesting Q&A with Bob Parsons, founder of Go Daddy, the domain-name registration company that has become famous for it's provocative TV commercials featuring scantily-clad women. Parson's image as a rebel sometimes overshadows the fact that he is a savvy businessman who worked his way up from a job in a steel mill to become CEO of one of the biggest Internet companies. In the interview, Parson discusses those notorious ads, how he got his start in business, and what he sees as the future of domain names. As he predicts, "We all have a physical address; we're all going to need an address in cyberspace. They're becoming increasingly important. I believe we'll get to the point where when you're born, you'll be issued a domain name." For a closer look at a day in the life of Bob Parsons, check out this Way I Work.

Incubators party like its 1999. This month's Inc. magazine has two big features on the resurgent popularity of business incubators, which saw their heyday in the 1990s but which have now staged a comeback. (One article isn't yet available online, but Bill Donahue's amazing story about a Youngstown, Ohio incubator is.) Today, the Wall Street Journal carries its own story, reporting that the number of new incubators in the U.S. has been growing eight to 10 percent annually for the past five years. Tracy Kitts, vice president of the National Business Incubation Association, tells the Journal that the trend is largely driven by high unemployment and a lack of adequate financing.

Would you like your genome with that shampoo? A San Diego start-up will begin selling genetic tests that evaluate an one's risk of getting different diseases, according to the New York Times. Walgreens will sell a saliva collection kit from Pathway Genomics for $20 to $30. Consumers will then be directed to mail in the kit and visit the company's website to order specific tests, which cost an additional $79 to $249, The Times reports. "It's more consumer awareness than we could get from advertising online," a Pathway executive told the paper.

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