The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
From Infield Salespro:
eContent, Show everything.Securely access your Salesforce Content and Chatter files on your iPad. Available for Professional, Enterprise, Unlimited, Performance and Developer editions using iPad 2 or later with iOS7. Group edition is not supported.You do not need to install an App on Salesforce. Just install eContent from the App Store and securely login with your Salesforce creditentials. This app is 100% free, fully functional, ad free and there's no subscription fees in the App Store, no in-app purchases and no Salesforce subscription fees.eContent enables you to securely access files on your iPad, including Word, Excel, PDF, Images and Movie files. Plus one click makes files available on your iPad for mobile access anytime, anywhere, with or without an internet connection.What happens when a new file has been added to your Salesforce Content? What's happens when a new Version has been add in Content? eContent syncs with Salesforce automatically so you have access to your Content files with version control. eContent is an ideal solution for sales reps and anyone who needs access to Salesforce Content on the iPad.