Ipod app questionn! :)?

Well you don't have to install any apps for a diary thing. iPods come built in with a "notes" application which lets you type notes/memories etc. It's pretty convenient and the notes can be shared with all of your friends. Well you can't have password for your "diary" but you can have a passcode for your iPod so you can lock it and nobody can access your data without the code. All you have to do is got to settings