These 9 hot startups looked like total failures at first - then they exploded

Then: Venmo launched in 2009 to let users text a band they liked and get an MP3 in return.

Now: After realizing that they had built the framework for a killer app, they built the modern Venmo: An app that makes it super-simple to pay money to your friends. And it paid off, with PayPal purchasing Venmo for $26 million in 2012.

Then: Justin.tv was founded in 2007 as a place for users to broadcast live content.

Now: Spin-off Twitch.tv, a place for video gamers to stream to their hordes of devoted followers, proved to be the fastest-growing part of the business, and the company refocused around it. It paid off, too, with Amazon purchasing Twitch.tv for $970 million last year.

Then: In 2010, dotCloud was founded as a company that let enterprises more easily run their applications in the cloud, but it never really caught on.

Now: By refocusing on the namesake container technology, Docker has become a powerhouse — developers love it, and venture capitalists just gave the company another $95 million in funding.

Then: Zimride started life in 2007 as an app designed to help students at his school, UC Santa Barbara, find carpools for the long-distance rides back home.

Now: In 2012, Zimride spawned an offshoot company called Lyft, a car-on-demand app that presents the juggernaut Uber with its most direct competition. By 2013, Lyft was the rising star, and it ended up selling the Zimride assets to Enterprise, which earlier this year decided to close it off to everyone but businesses and schools. Meanwhile, Lyft is fighting the good fight with 2.5 million rides per month.

Then: In 2014, Kayvon Beykpour and Joseph Bernstein had an idea for an app called Bounty, that would let users request to see what anywhere in the world looks like right now.

Now: Periscope took the basic idea behind Bounty — see what's going on in the world right now — and make it all about live-streaming videos. Twitter purchased the tiny startup this year for around $120 million before it even officially launched.

Then: Bettir was a connected blood pressure monitor app under development in the prestigious Y Combinator program. One weekend, the Bettir team put together an app called Magic that would let users order whatever they want, so long as it's not illegal.

Now: Magic had a tremendously successful launch, with users queuing up in virtual lines to get in on it, leading the Bettir team to refocus its efforts. And just a few weeks ago, Magic reportedly landed a Series A round of financing of $26 million at a $40 million valuation.

Then: Co-founders (and roommates) Alexis Ohanian and Steve Huffman originally connected to make a site called "MyMobileMenu," a mobile food ordering website. But when they applied to the prestigious Y Combinator startup accelerator program, famed investor and advisor Paul Graham told them not to bother, giving them the new idea of "a front page for the Internet."

Today: With 174 million users as of last year, you probably already know the deal with social news site Reddit. Reddit launched in 2005, got acquired by magazine conglomerate Conde Nast in 2006, and spun back out as a private startup in 2012. In 2014, it took in $50 million in funding from Snoop Dogg and Jared Leto.

Then: Dodgeball was a graduate thesis project at New York University by Dennis Crowley that let users check into places they were at, sending text messages to your friends in the doing. It got purchased by Google in 2005 and launched in 2008.

Now: After Google shut down Dodgeball not long after launch in 2009, Dennis Crowley took his ball and went home, taking the core technology behind the service and building a new company called Foursquare — which he had apparently always wanted to call it. Foursquare isn't as buzzed about as once it was, but the company is still doubling its revenue every year, says Crowley.

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