Im guessing he doesn't have any notifications of texts or missed calls. It should have them stock...check the top bar, where the time and battery is, on the left is where you will see all notifications, and you can drag the bar down to see the notifications in detail.
I think maybe he's meaning a reoccurring audible notification? I run into the situation where I miss a call, and the phone is somewhere where I'm not looking at the device itself. Unless I look at it...how do I know I missed something? I tried the Miss Call App, but I couldn't get it to work quite right. With that app you can setup reoccurring vibration or audio alerts. Say every 15 minutes is Beeps or something. The other problem I am having with the Miss Call App is you have to add Contacts individually to be notified about, so if they aren't in the list or not in your contacts it's not going to trigger a notification.