Have you ever stopped to think about how much sensitive information lives on your iPhone? From passwords and financial details to personal reflections and work notes, your device is a treasure trove ...

This week a reader writes, "In [a recen] column you mentioned that you keep some of your passwords in your iPhone in a locked note. Could you please explain how one locks a note? It sounds so useful.

Apple's no stranger to packing its apps with handy features, and the simple Notes app is no exception. Step up your game with these tips and tricks.