iCloud Drive is Apple’s essential connection between all your devices, Mac, iPhone, iPad, even your Windows PC.
While the cost of storage seems expensive in comparison to other online storage services, its advantage is that it works natively across all your devices.
You can use it to maintain access to all your documents and other items across your Apple devices, Macs, iPhones, and iPads. It also works with Windows using an application. Better yet, it works to ensure all your items are up to date across all your devices.
You need to be running iOS 13 or later or macOS Catalina or later on your iPhone, iPad, or Mac. A PC must run Windows 10 to access iCloud for Windows.