I have had this problem for years! I have 2 Apple ID's and really wish there was a way to merge them. My store Apple ID has a old gmail.com address that was hacked and closed years ago so I no longer have access to that email which is really not an issue. All my app store purchases are under that ID however. I have a different Apple ID under the old mac.com address that is used for iCloud. I do have access to that email so it's fine as it is.. My issue is now even worse with passbook. For instance if I download the Apple Store App it automatically logs me into the gmail.com app store account (as it should) BUT my Passbook info is tied to my mac.com iCloud account.. I have this issue in several different areas. I had a thought that I might be able to just use Family Share and share my gmail.com purchased apps with the mac.com iCloud account BUT Family Share is set up using iCloud... Round and round I go..... Edit to add: Okay, I signed out of my mac.com iCloud account and then signed into iCloud with the gmail.com account. I then added my mac.com to family share and accepted the invitation on my Macbook (which was still logged into the mac.com iCloud account) After that I went back to the iPhone and logged out of the gmail.com iCloud account and back into the mac.com account. Then I signed out of the gmail.com Apple Store account and singed in with the mac.com account. Is your head spinning yet???? LOL I might have this nailed down now to where I can use just the mac.com account for all my app purchases (it's now tied to the gmail.com App Store account) and my iCloud using ONLY the mac.com account on both.. I haven't tested Passbook yet and my fingers are crossed this actually works.. It's been a pain in my neck for years! Good grief, seriously Apple??? Edit 2: All iOS apps are fine for family share BUT on my Mac I have one paid app that won't and it's my most used app... Tweetbot! YAWN! Tweetbot only allows family sharing if it was purchased after June 3, 2014 but I purchased it years ago the day it was released... I have emailed the developer to see what can be done and I hope I get a favorable response..