Statistics and goals
Opens, visitors, screens — and whatever you decided to count.
Where: More → Statistics.

It shows opens, visitor counts and which screens get looked at. Counting is anonymous: visitors are distinguished within one day and one app, and no identity is stored.
Goals are yours to define. Put the Track goal action on a button and name it in plain words — “Tapped Order”, “Opened cart”. It appears in the statistics as its own line, and you start seeing not just how many arrived but how many got to the end.