Read/Write to iCloud

Due to Apples policy that any purchases have to be available on all the users owned devices, I need to store a value on the users iCloud so I can keep track of their purchases.

I am using Ionic, and wondering if there’s a useful Cordova plugin that will do this job?

I have read that BackupWebStorage may work, but am struggling to find examples.

Question

Please can anyone advise how I can access the users iCloud?

Thanks