Did you know that on iOS5 on the iPad, you can actually split the keyboard into two? This can be useful for typing with your thumbs if you are holding the iPad with both hands.
To do so, press and hold the keyboard icon on the on-screen keyboard. An option will appear, allowing you to split the keyboard into two. Alternatively you can drag the keyboard icon up across the screen until the keyboard splits up. Still another way is to simply put two fingers around the center of the keyboard and simultaneously drag them apart in a splitting motion.

Want to do a quick currency conversion? You can use Google for that. Simply type in the amount in the original currency, then the currency you want to convert it to.
introduced the concept of using multiple "Desktops" (previously called "Spaces") using Lion's Mission Control application. Using Mission Control, you can specify which desktop applications will automatically open in which desktops by default.
If you use an iPad, there is a switch conveniently located at the right side of the device which you can set to either lock the orientation of the screen or to mute the audio when you slide the switch—depending on your preference.
If you, for example, install multiple media player applications on your Android device, you’ll find that Android will give you the choice of which application to launch by default when you open a media file or document. However, you may later want to change this default setting.
Ever surfed for the number of a pizza place on your iPhone and just wanted to dial the phone number straight from the webpage? If you are using the default browser on your iPhone, which is Safari, that's no problem at all.
If you are using Internet Explorer and Windows 7, you may have noticed that when you mouse over an IE browser window, a preview of the open tabs in the browser is shown. While this is useful to give you an idea of the sites you have open, it can get annoying if you have multiple tabs open at the same time. If you would prefer to disable this feature, you can.
A very useful feature in Microsoft Office is called "AutoRecover", which automatically saves your document at specified time intervals so that in case of an application or system crash, Office can recover its latest version.
Leaving your computer for a short time but don't want anyone peeking at your desktop or files? Simply lock it. When you lock your desktop, anyone who wants to use it will have to log in using their username and password.

