Unfortunately, the only "somebody" who can create an app for that, is apple, as it would control one of their native apps. Better yet, they could (but won't) allow you to create users, so different family members can have limited or different access to various apps and info. They won't do that though, cause they want everyone to buy their own iPad. At least they should allow "YourName" and "Guest" so you can leave it out at a party without jeopardising your email, dropbox, and other private info.