userspbox has 30 million today. a lot of them use dropbox to get work done.cuments is a lot of office document. creating awesome experience around office and dropbox working together. they can take the office documents and edit them on mobile devices and on the web. how does it help dropbox's business? >> the more productive people are, the more engaged they are with the service, the more utility they get out of dropbox. >> another big move by microsoft is making office free on mobile. how big of a surprise is that to you? >> i think it's incredibly valuable to people who want to be productive. getting access to the best product there is is exciting. it's an incredible move up for them. the interesting things i read about dropbox is you are part of the shout oh -- shadow ip phenomenon. it's not officially used by my employer. how do you come out of the shadows and how much of that is part of your strategy? >> we have incredible success with our business product. growth in the u.s. sector alone. like hearstompanies and news corp.. there's something like 40 mil