Apple - How to restore individual app data from iCloud while keeping all the other apps installed and new data created since the last iCloud backup?
My own answer will be not applicable to every situation, but here is how I solved the problem.
All the data I needed from app in question (X) can be easily extracted once the app (with its data) is installed on the device.
So I did the following:
Backup the latest state to iTunes (saving a previous backup with "Archive" just before doing that)
Restore to the previous iCloud backup where the X app was still installed and had data
Extract all the data I need from X (I'm my situation, via iTunes > (my device) > Apps > Documents section
Restore back to the latest iTunes backup made in step 1
Re-install the X app in question from the scratch.
I ended up purchasing a third-party piece of software for this... iMazing (https://imazing.com/) was able to back up and restore the application data for an app from one device to another. They have a blog post that describes how to do this: https://imazing.com/guides/how-to-export-backup-and-transfer-ios-apps-data-and-settings
I was glad that it worked, basically I had something that my daughter produced when she was little in a kids app and I wanted to make sure that it was preserved, the app itself has been discontinued and does not have any sort of export/import functionality.
- Connect the source device to iMazing
- Go to "Manage Apps" and then the "device" tab
- Select your app and click the "Back up" button
- Connect the target device to iMazing
- Again, go to "Manage Apps" and click on the "device" tab
- Select your app, click the "down arrow" drop down, and then the "Restore App Data" option
For some reason, it made me shut off "Find my iPad" for the restore procedure (I was able to turn it back on afterwards without any hassle). Also, you can download iMazing for free, you have to purchase a license when you get to the "restore app data" part.