iPad: One of the problems with sharing an iPad around the house is the lack of multiple user accounts, Our Pad manages to solve the problem in an official capacity by letting you switch and browse accounts inside the app.
Currently, Our Pad supports Facebook, Gmail, Hotmail, Yahoo Mail and Twitter, but since this is an approved app, it doesn't work at the root of the operating system, so you have to launch it first. Each user gets an Android-like unlock pattern to get into their account, and for the especially private, no other users can view which accounts other users have. It's not as good as Apple allowing multiple user logins, but it works well enough so people who share an iPad don't have to constantly log in and out of social networks and emails when they hand it over.
Our Pad [iTunes App Store]