iCloud Backup and app data

I ran into a strange problem a couple of days ago. I noticed that the backup size for my iPad, which I have been backing up on iCloud for months, suddenly shot up from 650 MB to 12+ GB. I was surprised to see this as I hadn’t added any new apps/data that could explain the change in size nor changed any settings. Upon digging around I realised that around around 12 GB of the backup was taken up by Books. I do have books in the Books app (ones which are sideloaded and not from the Apple Books Store) totalling to that amount but have had them there for months. I don’t understand why they suddenly started taking up space in my iCloud Backup. Disabling Books in the iCloud > Manage Storage > Backups > iPad > Choose Data To Back Up helped me shave off the 12 GBs from the backup but this option had always been enabled and so I don’t understand why it only started taking up space recently.

I am also confused about how app data works with regards to iCloud Backups in general. I have significantly more data in VLC, for instance, but none of it is being backed up to my iCloud Backups even though I haven’t disabled VLC under both Apps Using iCloud and under the aforementioned Choose Data To Back Up in the device iCloud Backups settings.

Apple’s primer on iCloud Backups refers to purchased content (“Your iCloud Backup includes information about the content you buy, but not the content itself”) but isn’t clear on how app data is handled. I’d be thrilled if someone here can shed light on what is happening. Thanks!

Off-topic!
How do I side-load books to Books on my iPad (I haven’t got access to a Mac/XCode), and do the side-loaded books sync to other devices?

I add books by simply dragging them into Books on Mac (sorry, I know you said you don’t have Mac, but this is how I do it). Then, they sync on all devices.

According to Apple, stuff that is being saved to the Books app is automatically being synced across all your devices as long as iCloud Drive is being used:

I have no idea or explanation why the iCloud Drive had not been used before in your case…

Books that you buy from Apple are not being stored on iCloud Drive, they come directly from Apple’s Book store when being re-downloaded (as far as I know).

App data should be in iCloud as long as iCloud is enabled for the app.

You should be able to add any file the Book app can handle via the Share Sheet.

How? It is explained here.

1 Like

I have several hundred non-Apple, non-DRMed ePubs saved on my Mac. I drag-n-drop them into Books and they sync to iOS. I could keep them in iCloud Drive though, if I wanted easy access on iOS:

• Load ePub files into your iCloud drive on your Mac/PC.
• Open iCloud drive on your iPad, your files should be there.
• Select the file you want to read in Books.app.
• Select the share icon in the top right corner.
• Select ‘Copy to Books’

Thanks for your post @Christian. I have, and did earlier as well, Settings > Books > Syncing > iCloud Drive in the switched off state. The books were taking up space as part of my iPad device backup on iCloud.

Sorry, I should have read that more carefully… :slight_smile:

I have no idea why those books did not take up space before… iCloud Backup should behave exactly like that: everything that is not already in iCloud should be backed up as long as iCloud backups are enabled. What you can do is disabling stuff manually to prevent those backups from happening for your sideloaded book by deselecting iCloud - Manage Storage - Backups - YOUR DEVICE - Choose Data To Backup as you already have done.

More at:

1 Like

No worries, I asked how you do it :slight_smile:

Thank you. That’s good to know. Interestingly, apps seem to have leeway over whether app data is backed up to iCloud or not. VLC, for example, doesn’t backup user added files to iCloud. I didn’t know this before and so was confused.

To add to the confusion, I guess that if I were to enable iCloud Drive under Settings for Books then the side-loaded content in question would get backed up to iCloud Drive and not be a part of my iPad’s iCloud Backup. It would still end up taking up the same space on iCloud though. Would I be correct in assuming this?

I think that you are correct in your assumption. Apple’s explanation about iCloud Drive and iCloud Backup sounds exactly like that. If you really want to be sure, you might have to try it. :slight_smile:

Regarding VLC:

We explicitly opt-out all media synchronized to VLC for iOS. Most users only have 5GB of iCloud storage and that would be completely filled with just a single movie or few TV show episodes.

There is no option to enable backup of synchronized content to iCloud.

Source: https://forum.videolan.org/viewtopic.php?t=131189

So, basically VLC’s media content that is being stored locally is not being classified as app data, but as media data comparable to temporarily cached data. Which leads to the conclusion that it is not a good idea to ONLY store media data locally in VLC on an iOS device. You need a backup somewhere else.

I think Amazon Prime Video, Netflix and so on do the same. Otherwise, their apps would be responsible for basically filling up all of the iCloud space that is available to regular users. And that would lead to the fact that the usage of iCloud backup would be basically impossible for standard plan users as soon as they have VLC or other media players installed.

1 Like

Thanks much @Christian :slightly_smiling_face:

1 Like