You can access a file anywhere, any time by marking it as a favorite. Specifically, this does the following:
You can also mark a file as a favorite when you preview it by tapping the star at the bottom of the screen.
Once downloaded, you'll be able to access your favorites at any time. To ensure you have the latest versions, Dropbox will update them automatically if you're on a Wi-Fi network. If you're on a cellular (3G or 4G) network and some files have changed, tap each file to open it and get the latest.
If you have your personal and business accounts connected, you will be able to access all of the files you mark as favorites from the same tab. The Favorites tab allows you to view all your favorite files together or separate them out by account, so you can keep your personal and work data organized on the go.