If every time we add a new release (An) with n is the number of new features, we call m is the number of features which were already there in the app. The cost for implementing n(A) (n features for A) into original Product (with m features implemented),
The worst case would be up to O(n*m)
And It is a timing boom strategy.
Original photo: http://bigocheatsheet.com/
Modified: me.