SkyDrive Pro is for your work files while SkyDrive is for all of your personal files.
Windows 8 and iOS users received a treat today with the release of the SkyDrive Pro app. The consumer version of the SkyDrive application has been available for a long while, but this new release provides access to SkyDrive files and folders for business users using Microsoft'sor SharePoint Online services.
As Microsoft puts it:
"SkyDrive Pro is for your work files while SkyDrive is for all of your personal files."
To use the app, you need to already have a SkyDrive Pro account, i.e., it doesn't allow you to create an account within the app.
If you're a Windows 8 user, you can get it here: SkyDrive Pro
Or, just search the Windows Store for SkyDrive Pro.
If you're an iOS user, you can download SkyDrive Pro from iTunes: SkyDrive Pro for Office 365 subscribers