适用于iOS的合奏：我应该使用哪种类型的iCloud后端？

I wish to support an iCloud backend in my Ensembles based app so users can sync using their built-in iCloud account. However, I'm not sure if I should use the iCloud Drive backend, or the CloudKit backend, as both of them seem to allow syncing using user's iCloud account.I wish to support an iCloud backend in my Ensem