iOS 9 update will be out next month and it has got some extra features for Apple lovers. Till now Apple didn't introduced a app for iCloud Drive. We had to log in to iCloud account from browser to access it , but now in iOS 9 Apple has introduced iCloud Drive app as a hidden feature. You can enable this feature to get iCloud Drive on your home screen.
How to enable iCloud Drive app:
1:-To enable this feature go to settings
2-:In settings go to iCloud
3-:Then go to iCloud Drive
4:-In your iCloud Drive setting , slide the toggle next to Show on home screen
This way you can enable iCloud Drive app to show on your home screen and can access it directly.