iCloud Drive stores your spreadsheets, presentations, PDFs, images, and other kinds of documents so you can access these documents from any of your devices set up with iCloud. It allows your apps to share documents so you can work on the same file across multiple apps and collaborate on them with others in real time.
iCloud Drive works with iPhone or iPad using iOS 8 or later, Mac computers using OS X 10.10 or later, and PCs with iCloud for Windows. You can also access iCloud Drive through iCloud.com.
To access iCloud Drive, you must be signed into iCloud with your Apple ID. iCloud Drive works with supported apps including Pages, Numbers, Keynote, GarageBand, and some apps from manufacturers other than Apple.