Let me show you how to add a Google account to a Samsung Galaxy SIII so you can read you Gmail email, download apps from the Play Store and synchronize you Google Documents.
Nexus 4 smartphone comes with a bunch of Android widgets you can add to one of the screens. Let me show you how to add a widget to a screen and how to customize it.
iOS6 comes with a great new feature you can use to password lock an app or only a part of the app so you can hand over your iPhone to other people without worrying they will do or find something you don't want.