As an Office 365 administrator, you can use the user software page in the Office 365 admin center to allow or not allow users to install Office software from the Office 365 portal. For example, you might want to let users install Word, Excel, and PowerPoint, but not Visio. Whatever you decide to do, your choice applies to all users.
For more information, read the TechNet article:
- Choose the Office software that users can install from the Office 365 portal
http://technet.microsoft.com/en-us/library/jj219421(v=office.15).aspx
kurtsh
Kurt Shintaku's Blog 