I HAVE CREATED A NEW WAY TO INTEGRATE UNITY WITHIN AN EXISTING IOS APP. YOU CAN FIND THE POST HERE.
The problem
After my previous blog post on how to sandbox an iOS app inside of a Unity project, I got some questions on how to do the same but put Unity inside of an existing iOS app.
After playing around with it, I found a solution which works well for me to add Unity app in an existing iOS app.