15 of the fastest growing startups in the world still flying under the radar

Company: SkyGiraffe

Growth rate: ~9%

Last funding: a $3 million early stage round in February (at a 1.77x multiple)

Every company these days is writing custom mobile apps and Israeli company SkyGiraffe helps them easily build them, it says, without needing to hire expensive software developers.

Company: Inkshares

Growth rate: ~9.5%

Last funding: an $870,000 seed round in December (at a nearly 7.94x multiple)

Inkshares is a Kickstarter-style crowdfunded book publishing platform in San Francisco. Authors pitch their novels, readers vote by agreeing to buy the book, and with enough vote-orders, Inkshares publishes the book.

Company: Socialight Analytics

Growth rate: ~9.5%

Last funding: an $80,000 seed round in October (at a 1.69x multiple)

Socialight is a recent graduate from 500 Startups based in New York. It sifts through social media to analyze what particular sets of users are talking about (customers, competitors, etc.) and then offers specific suggestions to the business based on what it finds.

Company: Confluent

Growth rate: ~9.8%

Last funding: $6.9 million early stage round in November (at a 5.44x multiple)

Confluent was founded by former LinkedIn employees who built a software project called Apache Kafka and gave it away as a free and open-source project. LinkedIn used it to collect data from all over its network.

Now the startup is offering a commercial version for other businesses to use. Confluent is in Mountain View, California, and is backed by LinkedIn and others.

Company: Fieldbook

Growth rate: ~10%

Last funding: A $500,000 seed round in April (at a 3.13x multiple)

San Francisco startup Fieldbook lets you create a database as easily as you create a spreadsheet. It's intended for people that use spreadsheets to do things that a database really should do, like track incoming sales, manage a recruiting process and so on.

Company: Krux Digital

Growth rate: ~10%

Last funding: $35 million series B round in June (at a 12x multiple)

San Francisco startup Krux helps marketers, publishers and agencies consolidate the data they have about their customers to show the customers more relevant content.

Company: Notey

Growth rate: ~10.5%

Last funding: $1.6 million in February (at a 6x multiple)

Notey is a Hong Kong startup that wants to help people discover great original content and blogs on the internet to help people research topics like, for example, when they are planning a far-flung travel itinerary.

Company: Rain

Growth rate: ~10.8%

Last funding: $100,000 in August (at a 1.48x multiple)

RAIN is 500 Startups company based in L.A. It offers an ad network that helps small businesses reach local customers by targeting ads based on a mobile device's GPS location.

Company: Peel-Works

Growth rate: ~12.6%

Last funding: $2 million early stage round in July (at a .92x multiple)

Peel-Works is cloud based service based in Mumbai, India, that helps small and mid-sized businesses build a smarter salesforce through data and analytics.

Company: Mesosphere

Growth rate: ~13%

Last funding: a $36 million early stage round in December (at a 23.56x multiple)

Mesosphere is a San Francisco startup building what it calls a new kind of "data center operating system" that takes all the machines a company uses in the data center and makes them work like one big machine.

Company: Deem

Growth rate: ~14%

Last funding: Deem became a so-called "unicorn" startup with a $50 million round (at a 47.19x multiple) in July that valued the company at $1.4 billion.

Deem is a cloud-based, integrated suite of travel, expense, and purchasing management software based in San Francisco.

Company: Blitzen

Growth rate: ~16%

Last funding: undisclosed

Blitzen is an Ontario, Canada, startup that lets you build forms online, connect them to cloud apps like Google Apps, MailChimp, Salesforce, and Box to easily automate work processes.

Company: AppAnalytics

Growth rate: ~19%

Last funding: A $300,000 seed round in January (at a .96x multiple)

Every business is building mobile apps these days and San Jose, California, AppAnalytics lets businesses track how those apps are performing. It's claim to fame is a "heat map" that aggregates the data into a simple chart.

Company: ZoomCharts

Growth rate: ~37%

Last funding: A $620,000 early stage round in December (at a 1.96x multiple).

ZoomCharts offers tools that lets companies easily turn their data into charts. It's an especially popular resource for Web developers and programmers building mobile apps.

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