Complex sentence: CloudKit is one method for App developers to integrate access to Apple's iCloud servers and it provides authentication, a private and a public database, and structured asset storage services for developers of Apps that make use of iCloud services.
Split into simpler sentences: CloudKit is one method that App developers can use to integrate access to Apple's iCloud servers. It provides authentication, a private and a public database, and structured asset storage services for developers of Apps that make use of iCloud services.