This article explains how to fix the “Unable to Download Application” Error when trying to download applications from the App Store.
*You need to have a jailbroken device with iFile installed from Cydia
-Click blue arrow next to “Downloads” folder
-Under”Ownership” change the “Owner” and “Group” settings to look like this:
-Under “Access Permissions” change all settings to look like this:
-User- Read, Write, Execute
-Group- Write, Execute
-World- Read, Execute