Restore App deleted from App Store
Okay, so this is a very confusing question.
This is the situation:
I recently changed to an iPhone 7 (iOS 10.2), but there is an old app on my iPhone 5S (iOS 10.1.1) which I would like to have on my iPhone 7. So the App has been pulled of the App Store and is not showing up anymore in my Purchased tab of the App Store. When installing the old backup from my 5S to my 7 during the initial setup, the app was actually being downloaded on my new 7. For some weird reason I "Prioritize Downloaded" it with 3D Touch, after which the app decided to delete itself instead of downloading itself. I have no idea how to get this single app on my new iPhone. Is there some third-party software to do this? I am not wanting to setup a whole new backup for just one app, as I would lose all my other data since the time I got the 7.
Thanks for the help in advance!
iPhone 5s, iOS 10.1.1, null