Change your Voice and Caller ID.
CrazyCall is the ultimate tool for making prank calls and fooling your friends. You can change your CallerID (SPOOF), so when you call someone he sees on his Caller ID display the number you selected. You can also change the pitch of your voice (Voice Changer) for deep and creepy or high and funny.
To use the app, your phone will dial to an International or premium rate number. The call rate vary depending on your carriers charges.