The app makes it ridiculously easy to retrieve your iOS device's Advertising Identifier. It is helpful for anyone debugging mobile apps especially people working in advertising.
Ratings and Reviews
App is stuck
App is not working, please rollback to old version. (stuck on "allow notifications question")
The reviews are correct that you cannot copy from the app. However, if you tap the "compose" icon at the top right of your screen, it will open up an email containing all of the relevant data, which you may copy from there until they patch this bug.
Simple app that does what it advertises.
With Family Sharing set up, up to six family members can use this app.