7. Social Networking Sites

Social networking giants Facebook and Twitter are both among the highest profile technology companies in the world. Both have a massive user base: Facebook has more than 1.3 billion monthly active users as of its most recent quarter, and Twitter reported 284 million monthly active users in its most recent quarter. It wasn’t too long ago that Facebook and Twitter were small startups. Although the industry has already exhibited tremendous growth, IBISWorld expects growth to remain strong. Just this August, a relatively new social media company, Snapchat, was valued at $10 billion, based on an investment by venture capital company Kleiner Perkins Caufield & Byers.

6. Smartphone App Developers

Like in many other growing industries, the production costs of mobile app development are very low, spurring high growth rates. The industry’s revenue grew by at an annualized rate of nearly 50% from 2009 to 2014, reaching $9.7 billion this year. Mobile apps are particularly popular in the United States, which leads the world as a source of smartphone app revenue according to International Data Corporation (IDC). Not only has the mobile app developer industry grown dramatically in recent years, but the industry also has low barriers to entry. Arguably, anyone with a computer and Internet access can potentially develop a successful smartphone application.

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5. Cider Production

The hard cider production industry grew at an annualized rate of more than 50% in the five years through 2014. Still, cider production remains a relatively small industry, with $293 million in revenues as of 2014. By contrast, craft beer is a roughly $4 billion industry, according to IBISWorld, while major breweries overall are far larger still. Thanks to fast growth, cider’s resurgence has captured the attention of big brewers, such as MillerCoors and Anheuser-Busch, which have themselves recently launched cider brands to attract drinkers.