iCloud Drive app
iCloud Drive, Apple's cloud storage service, is available as an app on the home screen in iOS 9. You can use it to share files across your iPhone, iPad, and MacBook.
Earlier versions of iOS let users access their files from iCloud, but iCloud Drive was only accessible through specific Apple apps like Pages and Keynote.
When you turn on the iCloud Drive app and access your account, you'll notice your documents organized in folders. You can move or share files from within the app; to edit, you'll have to export via the Share button and choose an app compatible for editing.
The iCloud Drive app is not automatically enabled. Switch it on by going to Settings > iCloud > iCloud Drive and select Show on Home Screen.