How to transfer a discontinued app from one iPhone to another iPhone
I have an app called "Lono" to control my sprinkler system on my old iPhone with iOS 11. And when I upgraded to a new iPhone with iOS 12, and want to restore my phone via iTunes backup, and I realized that this app "Lono" is removed from the App Store and no longer available, and I do not have the app backed-up in my iTunes! I tried to downgrade my iTunes from 12.8 to 12.6 to bring back the "App" tab to transfer the app from my old phone to iTunes. However, transfer purchases is no longer working as my old phone has iOS 11...
In this case, how should I transfer this discontinued app from my old phone to new phone?
Thanks!
iPhone Xs, iOS 12