Dropbox for Teams. That's a new service to allow synchronized file sharing among businesses, announced Thursday by the online storage Relevant Products/Services company used by millions.

The company said that, with the new services, "business Relevant Products/Services can now experience the same ease-of-use" that 45 million individual users enjoy, along with "new administrative controls, centralized billing, phone support, and plenty of space for everyone on the team."

A Growing Category

With Dropbox for Teams, users employ the same interface as individual Dropbox -- saving any file to the Dropbox-enabled folder on the user's local machine. New files are then immediately synced across all devices that have a Dropbox folder installed, and the service is available for Windows, Mac, iOS, Android and BlackBerry platforms. Files are available locally when the user is offline, and users can view an unlimited version history for any stored file.

Dropbox is one of several cloud Relevant Products/Services-based storage companies in a rapidly proliferating category, including YouSendIt.com, Box.net, Mozy, Windows Live SkyDrive, CX.com, 4Shared, SpiderOak and, to some extent, such services as Apple's iCloud and Google Docs. Citrix Systems recently acquired storage service ShareFile, and Research In Motion has purchased NewBay.

The key driver is that many users have multiple devices, including a computer, a tablet and a smartphone, and being able to exchange and sync files between them, and with colleagues and friends, can be a significant housekeeping effort.

Forrester Research, for instance, has found that almost 60 percent of adults who go online have at least two Net-connected devices, and 3 percent -- more than four million users -- have at least nine devices.

Since high-speed connections are now common, online storage becomes a feasible method of exchange and management, as well as a ubiquitous backup system.

Administrator Features

The individualized Dropbox has met with some resistance among corporate managers, who are understandably nervous about company files residing on another company's servers.

But Dropbox is attempting to offer administrators of Teams some controls to help offset their worries. For instance, administrators have the ability to add or delete users. The company notes that the service is a secure Relevant Products/Services solution, with files stored on servers at Amazon data Relevant Products/Services centers with "bank grade" AES-256 bit encryption, as well as being backed up on users' local folders.

The Federal Trade Commission at one point received a complaint from a security Relevant Products/Services specialist that Dropbox employees had access to unencrypted files on its servers. The company responded that it prohibits employees from accessing user documents. In June, Dropbox suffered an outage for several hours, following a security incident.

The Teams service costs $795 a year for five users with one terabyte of storage, and additional users are $125 each. Additional seats come with an additional 200GB.

Started in 2007 in San Francisco, Dropbox has more than 45 million users in 175 countries. The company says a billion files are saved to its servers every three days.