When restoring iPhone backup, asked for *previous* iCloud accounts?

Question

I've been using my username@outlook.com Apple ID on my iPhone for over 2 years.

Prior to that I had username@gmail.com and before that I had username@yahoo.com as my prev Apple IDs.

When I'm restoring my iPhone backup, I was asked for my current Apple ID (the outlook.com - makes sense) but ALSO was asked for the passwords for the older accounts (unused gmail.com and yahoo.com based iCloud accounts).

I guess it's asking because I had apps purchases from those Apple IDs still on my phone so I just hit "skip".

Is there a way for me to

1. See which apps are still linked to my no longer used Apple IDs
2. Move those app purchases over to my newest Apple ID
3. Remove those older Apple IDs from future backups (so future restores don't bug me like this)

Answer 1

  1. See which apps are still linked to my no longer used Apple IDs

Whilst there's no 'list' of these apps, you should be able to notice apps which haven't been restored to the device, as these will be apps purchased with those Apple IDs. If you're watching the device being restored, you may notice such apps move straight from Waiting… to being deleted—this is a sign of an app which is not permitted to be installed.

  2. Move those app purchases over to my me Apple ID

There is no automatic process for this. You'll need to find apps which aren't installed and you remember being installed (or you see not being installed per the previous paragraph) and reinstall them, whilst being signed in to your newer Apple ID.

  3. Remove those older Apple IDs from future backups

As these apps have not been installed, future backups won't be aware of these apps ever existing and consequently you won't be prompted for the Apple IDs again.