Depending on the mobile device you use, there are a number of places to download and purchase apps. Though many of the apps are free, you will need to create an account for each store in order to download any apps.
The Blackberry App World storefront allows you to search for and download items for your blackberry device.
Be more productive and manage files on the go
With this app users can read, search, and share PDF documents. Open PDF files from email or the Internet. Universal app. Free
Dropbox is a cloud-based, shareable, virtual file system. Once you save your documents, photos, videos, and presentations to a Dropbox account you can view the items from any mobile device or computer. Dropbox provides up to 2 Gb of free storage. Universal app. Free
Google Drive lets you keep all your stuff in one place. Upload all your files from your computer - even the big ones - and you can access them anywhere. Universal app. You receive 5 GB free.
Documents to Go Premium- Office Suite
CloudOn brings Microsoft Office to your tablet and links it to your Box, Dropbox and Google Drive accounts. The built-in Adobe Reader and File Viewer lets you open and view virtually any file type, including PDF, JPG, PNG, GIF, etc. Universal app. Free