Hot startups don't often stake their reputation for innovation on how well their technology works with Microsoft Office, but that's exactly what Dropbox is doing today. The file-syncing service, one of the most valuable venture-backed private companies on the planet, is rolling out several Office-related features for businesses, including full-text search of Word, Excel, and PowerPoint documents, among other file types, and the ability for multiple users to simultaneously edit Office documents via Dropbox.

While Office itself stopped being synonymous with "cutting edge" sometime before the turn of the century, Dropbox's attention to Microsoft's flagship productivity software speaks to a deeper truth: People still use Office. Lots of people. And that reality, in turn, speaks to Dropbox's strategy for distinguishing itself in the (over)crowded field of cloud-based file storage, syncing, and sharing. While some competitors are banking on providing the most gigabytes for the least dollars, Dropbox is devoting itself to services that make those files more useful.

"Right now our focus is on slotting into people's basic workflow and making that really good," Ilya Fushman, head of the company's Dropbox for Business product.

More Service, Not Storage

This stands in contrast to Google in particular. Back in March, Google announced it was offering one terabyte for $9.99 per month. Dropbox for Business, by comparison charges $15 per month per user for a minimum of five users to split a terabyte among themselves, though the company says it will raise that limit to whatever users need if they max out their storage. Each additional user gets an additional 200 gigabytes to start.

On price alone, Google may seem the more obvious choice, but Dropbox's more casual attitude toward exact gigabytes per dollar shows where its priorities lie. The seven-year-old company hasn't gotten as far as it has—300 million users at last count—on price and space alone. Dropbox's rigorous attention to usability, starting with the Dropbox folder itself, has built a loyal user base who Fushman credits as the leading reason businesses are now embracing the service as well: workers are using it at work already. In shaping Dropbox for Business, that usability would seem to extend to meeting those workers where they already are, which is Office, while Google wants businesses to migrate to its own rival productivity suite.

>Whatever Microsoft's tribulations, Office is still everywhere, which is where Dropbox wants to be, too.

Other new Dropbox for Business features announced today include passwords and expiration dates for shared links and an API for shared folders that let developers create third-party applications for collaboration. Dropbox isn't averse to building its own applications on top of its own platform—the popular Mailbox app is one, as is Carousel, its slick photo-viewing and sharing app.

But for now, the company seems just as interested in making itself a platform for other people's apps, including Microsoft's. In yesterday's earnings call, Microsoft said its own cloud-based Office 365 gained a million subscribers during the quarter, up from 4.4 million three months ago. Whatever Microsoft's tribulations, Office is still everywhere, which is where Dropbox wants to be, too.