Have you ever imagine multi user account feature found in desktop operating system (Windows, Mac, Linux) that enable you to login using different user account now can be found on mobile operating system? Yes, Android 4.1.1 aka Jelly Bean, the latest version of Android operating system has this feature built in hidden code. It means you will never use this feature by default because this is not intended for general use. Google never announce it, there wasn’t any discussion about it during Google IO 2012. It might be still in beta and under testing and might be announced in next version of Android.
But if you have a rooted Jelly Bean, you will be happy because with a few extra command line on Android shell terminal, you can use this feature. Under android shell command line, you can create new user, view list of available users and delete users.
How to use:
Every user has different configuration for each application and also has different Gmail account. It means you can create additional user for use by others (eg. friend or family) with separated Gmail account. This allow you to limit the access to Play Store if you have Gmail account linked to Credit Card so other user can not buy applications without your permission. The additional users (non primary) also have limited access to Settings menu. They can only access Wifi, Bluetooth, Sound, Display, Security and About menu.