What different ways are there for apps to store data in iCloud and which are visible from the iCloud Manage Storage

Question

There seem to be a few different ways for an app to store data in iCloud (iCloud Drive Documents, Core Data with iCloud Sync, CloudKit Private Databases, Key Value Pairs etc) but I'm not sure if that's all. Which of these different types of iCloud storage appear to the user in the iCloud 'Manage Storage' menu (i.e. some apps don't appear at all whereas others list 'Documents and Data' whereas others list files that can be individually removed but don't appear in iCloud Drive)? I'm trying to figure out but the documentation's a bit vague on this.

Answer 1

Aaron,

There are three "Apple owned" places you can store data for an iOS device, on the device itself, in an iCloud Drive and/or in the iCloudKit database.

The iCloudKit database has within it three more places. Two of those are databases in the true sense of the word, so structured areas you can store information within, namely key/value pairs and CloudKit. A CloudKit database itself breaks down into two more principle divisions, public and private areas.

Their accessibility is governed on a user/app basis. So you as a developer can opt to use or indeed make your files accessible on them or not. The rules governing who can access what can be confusing, especially as they can/have been changing over different iOS releases.

The iCloud Drive is the most and least flexible, you can store everything on it but you cannot share anything within it, except with yourself.

The iCloud key/pair database comes next, except it is used exclusively by an application to store application state/preferences only [it has a very limited space], again you can share it with yourself only.

The CloudKit database comes next, again something that would be used on an application by application basis. So apps do not share databases and cannot access other app databases, unless they come from the same author and sharing is a built in functionality that has been explicitly intended.

That said, the CloudKit database has two distinct areas a private and a public one. The private area can be accessed by a single user of an app, the public area can be accessed by anybody using said app on any iOS device.

CloudKit documents are an area where Apple store documents from its apps principally, so keynotes, pages and numbers; although they have opened it up somewhat in recent years. They can be shared with other users too using on of the apps designed specifically to store data within the iCloudKit documents area. It is the closest you'll get to a dropbox under iOS, short of using dropbox fof course.

Finally you can store data on your iOS device itself and opt in to share that with others on the same device too thru Apple's files app, although that that is a very recent status quo, so only available for apps designed to run under iOS 11 explicitly opted into the new status quo.

All that said, Apple counts all the places as one in the same when it comes to storage limits, be warned if you want design/build an app using cloudKit storage; if Apple deem you did so recklessly, you won't get a foot in on the app store.

As final comment Apple security policies are designed as a general rule to ensure you as a user have quite fine grained control over who accesses their data, it was/is an intentional decision on their part to protect you from yourself. As a general rule, it works well; which is why you see almost no viruses under iOS.