Square

Square seeks to radically change the way people pay for goods. Instead of using cash, coins, and receipts, Square designed a device that plugs into the headphone jack of your smartphone or tablet and allows customers to swipe their credit cards to pay for goods. The company has had a profound effect on mobile sellers and small shops around the country by allowing them to accept credit card payments in a fast-approaching paperless economy.

Led by the quiet, intense Twitter co-founder Jack Dorsey, along with PayPal veteran Keith Rabois, Square has become one of the fastest growing startups in history. The company is now processing more than $8 billion worth of transactions annually, up from $1 billion in 2011. Although most of that revenue goes to the credit card companies, Square is reportedly valued at $3.25 billion based on its last round of funding, which included a $25 million investment from Starbucks. The coffee giant is also engaged in a long-term strategic partnership with Square, with plans to eventually process all of its U.S. credit and debit card transactions through the service.

Disrupting the behemoth financial world--which is highly regulated and insanely complicated--won't be easy. But Dorsey's passion for simplicity and attention to the smallest of design details have put Square on a trajectory that the old guard will have difficulty matching.

The biggest threat to Square may be its own accelerated growth.

Square Long Reads

Making Magic Out Of The Mercantile
When Square launched in October 2010, it was a mere dongle that plugged into iPhones, enabling anyone--especially small businesses--to accept credit card payments. No more. Square has since set out to transform the entire payments process

How Jack Dorsey's Square Is Accidentally Disrupting The Entire Payments Industry
Dorsey and Square COO Keith Rabois talk to Fast Company about their unintentional, design-driven revolution, what it means for the cash register space, the deals space, and the future of buying ... everything.

At Square, Jack Dorsey and Keith Rabois Are OCD About Design
Why the company's founders are maniacs for refining their product's design.

How Jack Dorsey Succeeds Through Simplification
"We have everyone you can imagine against us," says Jack Dorsey, the CEO of mobile credit card pay startup Square and cofounder of Twitter. But he is not cowed by fact that his startup is competing against banks with far more money to spend on pushing their products to market.

Square Brings Credit Card Swiping to the Mobile Masses, Starting Today
Now that Square is publicly available for iPhone and Android OS, with millions of card readers being shipped free of charge, Jack Dorsey tells Fast Company how his business model will disrupt the way you pay.