To determine what version of the Box for iPhone and iPad app you're using, go to your app's Settings and scroll to the bottom. The version number will be displayed at the bottom of the page:

which version of the app

If you're on a version of the Box app older than Box for iPhone and iPad 3.0, we recommend upgrading to the latest version of Box for iPhone and iPad. Download the latest version from iTunes

 

See What's new in Box for iPhone and iPad 3.x?