Trying to scare your friends??? Its almost April 1st and with new technology coming out, new and better pranks are made. Simply using apps or walllpapers. Its that simple!!

Step 1: Download

The first thing to do is to choose whether to download "cracked screen" as an app or wallpaper. I personally would choose an app as its got more specifications and it looks more realistic.
1.Application: For android: Go to market and download Better Cracked Screen
Check for other apps for other phones
2.Wallpaper: For iphone:
link 1 http://forums.macrumors.com/attachment.php?s=3970dfb3b493c8cc3f7e3c6c6c289d08&attachmentid=149410&stc=1&d=1229891183

Connect your iPod to your computer as you normally would with the USB cable.

Open iTunes if you don't have it open on your computer already. You will be able to access photo options from here.

Choose "Preferences" from the iTunes menu. This will pop up a tab where you will be able to complete step 4.

Click on the iPod tab in the screen that will open up after completing step 3.

Select the "Photos" tab in the "iPod" pane you chose in step 4.

Choose the "Synchronize Photos From" checkbox and select either "iPhoto," "Choose Folder" or "Pictures" (as in your pictures folder) from the pop-up menu.

Source
eHow.com http://www.ehow.com/how_2016287_put-pictures-ipod.html#ixzz1IdT7CyG7

For android/iphone and other phones:
link 2 http://3.iphonewallpaperclub.com/wp-content/uploads/2010/11/Cracked-Screen-iPhone-Wallpaper-Download.jpg&t=cfcdc3488ceecfa7c09a28979302b1fd

Copy link and paste it

You can choose your own ones in google :P

3. If its a wallpaper then save it on your phone(make sure you use the right resolution).

Step 2: Using It!!

4. After you have the app or the wallpaper on your phone its time to shock your friends!!!

5. The best way for it to look real is to view the "cracked screen wallpaper" through the gallery so thatthe icons dont ruin the prank!!!
For the app just test it out before you give it a try on your friends an your confident it will work. I reccomend to turn off vibrate for better effect

6. Enjoy the shock of your friends, colleges and even your teachers!!!