Want to make a cruel joke on your friends? Try this application. Select the image you want to display and define the trigger type. You can set it to display immediately after few seconds or be triggered by touch. That will allow you to run some other application. After the defined period of time the application will kick in and display some scary image, play the horror scream and vibrate. Just set the trap and hand over you phone to someone else. Then watch the reaction. Remember to set the volume to maximum. Then just hope your friends won't get angry at you.
Do not try this on someone with feeble heart.
If you like that one you might want to also try my broken display prank.
If you think something could be done better then please send me your comments. Hope you will have fun :D