Consider the modest PDF, for almost two decades now the de facto standard digital document format first described by Adobe co-founder John Warnock as the “Camelot” system – a file format independent of specific software, hardware, and operating systems in the early '90s.

These days, probably the main way most of us are reminded how often we use PDFs is that annoying red icon of the Adobe Reader Updater that pops up almost constantly on our computer screens.

Meanwhile, the problem with PDFs, for most of us, is they have not been easy to interact with – i.e., to create, convert, edit, sign, and share. They represent a relatively static type of format in a world where interactivity is key.

That’s where SoMA-based Nitro comes into the picture.

It’s developed ways for people to create PDFs from any kind of file, such as Microsoft Word docs, converts whole collections of files to PDFs in one batch, and open PDFs in browser windows, amoing many other features.

“We are not a PDF company,” Nitro's CEO, Sam Chandler, is quick to point out, “but a digital document company. We believe the format shouldn’t matter.

“PDFs are based in the past and the state of computing at that time, 10-15 years ago, when you could only share them via email. Fast forward to today – now there are other ways to share documents.”

Chandler started the company in his native Melbourne, Australia back in 2005.

“We wanted to help usher in a digital document revolution. We could see the wheels turning. We looked at the way the world was using digital documents, only using 5 percent of their interactive potential. No sticky notes, comments. Nothing like that.”

A few years into pursuing that revolution, Chandler relocated here, to San Francisco, in January 2009.

By then, his team had developed a product that was much more flexible and priced lower than Adobe Acrobat – the professional version of the free PDF reader most of us use, but they wanted to gain more traction with users.

“We started by naively thinking if we had a fair price point we could change the world. Within a few years, however, we realized we needed to release products for free in order to achieve scale.”

And so they did.

“When we released free Nitro Reader in May 2010 we quickly scaled to the point where now we have hundreds of thousands of paying customers and millions of free users. In the process, Nitro has literally helped create hundreds of millions of PDFs.

“The Nitro Reader is only free PDF viewing tool that also lets you create PDFs. In the two and a half years since release, 3.5 million users have adopted its collaborative tools, like commenting, underlining, strikethroughs, sticky notes, and a quick free way to add a digital signature. You just take a photo of your signature with an iPhone, add it to the Nitro Reader, and we can quickly size it to the right line in the file for signing.”

The company's moneymaker, meanwhile, is the Nitro Pro, priced at $119 with the complete set of features its 300,000 business customers need in working with PDFs. It’s a direct competitor to Adobe’s Acrobat.

But the Nitro team has a vision far beyond PDFs.

“Our vision is to make the format completely irrelevant,” says Chandler. “You won't have to be an engineer to manage it, either.

“Every conceivable popular platform and device will be folded into our plans. So you can work wherever you wish with whatever document you want on whatever platform you want. The interface will be tailored to each device.

“Our next chapter will be written in the cloud. You’ll be able to collaborate, comment, share back and forth across all the other formats.”

Nitro, which recently closed a round of venture backing, is already profitable, says Chandler, and employs 86 people here and overseas. It’s hiring and moving into larger offices on Bush Street soon.

As to the question of why they are headquartered in San Francisco, Chandler is direct: “If you're going to build a tech company this is the place to do it.”

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