Login as either Mitanin Trainer or ANM using the role toggle on the login screen. Both are demo logins, any username or password works.
As Mitanin Trainer: open a Mitanin, then either tick the four activities tagged MT you are confident about and hit Approve at the bottom, or tap into one activity to Approve/Reject it individually with a reason.
As ANM: same pattern, but scoped to every activity other than the ones tagged MT. Anything left unticked when you hit Approve is rejected and sent back to the Mitanin (you'll be asked for a reason).
Tap the language pill in the header (EN / рд╣рд┐рдВ) to toggle the whole interface between English and Hindi.
Tap the bell icon for sample notifications relevant to the logged in role.