Upgrading Your iPhone with Multiple Apple IDs

I recently received my iPhone 4S in the mail and was as excited as I imagine anyone would be when they receive the best mobile device this side of Romulus. I backed up my existing iPhone 3GS in iTunes and after going through the initial setup on the 4S hooked it up to iTunes to do the restore. When it was finished I flipped through my new phone and noticed that I was missing over two thirds of my apps. WTF! I tried backing up and restoring a few more times but no dice. The only thing I could figure was it must have something to do with my having multiple Apple IDs.

I have multiple IDs because I work at AOL and Apple at some point (not sure if they still do it) promoted AOL users being able to easily create an Apple ID with their AOL account. I also have another ID which I setup using my personal e-mail address. Sadly I unknowingly purchased apps and music on both accounts which led to this recent dilemma. I don't use iTunes (I loathe it) so almost every purchase I make is made directly on the phone. Never syncing my phone and my library made this even more complicated.

I did some research and the only thing I found was this statement from Apple:

"Apple IDs cannot be merged. You should use your preferred Apple ID from now on, but you can still access your purchased items such as music, movies, or software using your other Apple IDs."

Lame :/ There's a lot of talk about them allowing it in the future but for now it's not possible. Fortunately for the handful of people out there who have this problem and haven't figured out a workaround there is an easy solution.

I'm going to walk through how to restore your Apps but this also applies to Music, TV Shows, etc as well.

Open up iTunes and click 'Store' on the top menu bar. You should see 'View My Account (your.apple.id)'. Make a note of which account you're currently signed in as.

Now look under 'STORE' on the left menu bar and click on 'Purchased'. In the bottom right of the iTunes window you'll see a 'Download Previous Purchases ->' link. Click on that.

You'll get a nice page that breaks down all of your previous purchases by category. On the top right you'll see 'All' and 'Not in My Library' buttons. Click on the 'Not in My Library' button. You should get a list of all of the Apps that you've purchased but haven't synced up with your Library. In the bottom right you'll see a 'Download All' button. You can do this to make things easier on yourself or you can click the Download/Cloud button beside each App if you want to do them individually.

Once you're finished downloading everything you need on this account, click on 'Store' again on the top menu bar and then 'Sign Out'. Click 'Store' again on the top menu bar and 'Sign In' with your other Apple ID. Repeat the steps above to get all of your content downloaded to your Library.
Now click on your iPhone that's listed on the left menu bar and then click the Apps tab. Make sure 'Sync Apps' is checked. You should see all of your Apps listed here now. Click the 'Sync' button on the bottom right of iTunes and voila - you're all set!