I often hear the notification bell go off in my iPhone, but when I pull down the drop-down of alert events, I dont see anything which matches the time the alert went off. Is there a way to see what event caused the alert notification to go off?
In the settings, go to Notifications, and select Notification Center for every app with Sound selected.
Then chose to Sort Apps by time.
That way, when you hear the sound, just access your Notification Center, and the culprit app will be on top.