Box, previously known as Box.net, competes with services like DropBox, SugarSync (neither of which have official Windows Phone apps, though there are third party options) and SkyDrive (which does have an official Windows Phone app). Box is perhaps best known for its enterprise and collaboration focus, with an emphasis on security, partnerships with a number of big enterprise players (e.g. Salesforce.com and Google Apps), and an API that has created a rich ecosystem of third party apps (Quickoffice, eFax, LinkedIn, DataViz),
Box provides a free, single user, service plan (5GB of space), but there are also tiered pricing plans (for business and enterprise), which provides more space, support for multiple users, and additional features (faster uploads, additional security features, search tools, version history, and desktop sync).
The Windows Phone app allows you to access and view the content in your Box account. Each folder level gets its own pivot view with pages for files (listing folder contents), collaborators (shows who you have shared the folder with) and uploads (listing in progress uploads). Each file also gets a pivot view with pages for file (thumbnail and file information) and comments (from people you have shared the file with).
File management features include support for multi-select, folder creation, file/folder move/copy, and deletion of files/folders. From the toolbar you can search for files and folder by name (which shows a third pivot view, with pages for all, folder and files), share a file or folder (by email, social or messaging), and kick off a slide show of images.
You can download and view files from your Box cloud storage, but it's only worth doing so for formats that are supported by Windows Phone (images, PDFs and Office documents). However, there's no automatic re-upload if you make any changes (edited files must be saved to the phone or to SkyDrive). Furthermore, manual uploads are limited to images files, which means it's not possible to "round-trip" a document to the cloud (i.e. download, edit, and then re-upload). However, it is only fair to point out that this is due to the limitations of Windows Phone API library, rather than any restrictions imposed by Box (the same issue applies to Microsoft's own SkyDrive app).
Given the potential sensitivity of the data stored in Box cloud storage it is great to see support for an app specific pass code, which can be activated via the settings page. This will prompt for a pass code when starting, or returning to, the Box app, providing an additional layer of security. It would be great to see more apps, especially those that provide access to sensitive data and/or services, take this approach. [The only other WP7 app I've seen with a passcode feature is LastPass! - Ed]
It's also good to see that Box has taken advantage of Windows Phone's Live Tile functionality. You can also pin individual files and folder to the Start Screen for faster and more convenient access to key content. And, if you pin the Box app to the Start Screen, you get a Live Tile that, which, on its flip side, shows the number of updates other people have made to your Box content, providing a subtle notification about updated content.
Highly recommended for anyone with a Box cloud storage account.
Desktop, laptop, tablet, phone, you name it – with Box, you collaborate and share critical content anywhere, anytime, on any device. So now, you can: send an important file from an elevator, perfect that preso on the plane, comment on a coworker’s document from a taxi, view updates to your files instantly, proof a PowerPoint right before the big meeting.
The official Box app can be downloaded from the Windows Phone Marketplace for free.