Grand Theft Auto IV/Secrets

There are a large amount of secrets hidden in Grand Theft Auto IV. Some are simple passwords, and some are Easter Eggs, and a list of them can be found below.

Cell Phone Passwords
To use theses, pull up your cell phone in the game and dial the number. Certain cheats will disable Achievements.To enable them again, you will need to load a save where these cheats were not used to continue gaining achievements. (Calling ZiT and getting song information does not disable achievements.)

Computer Passwords
To enter these, enter them in the URL on an in-game computer. This will not disable Achievements.

Heart of the the Statue of Happiness
If you are legal to go to Happiness Island (steal a helicopter and fly there). Go to the feet of the statue of happiness and jump off; if you land on the top platform, then run to the doors and you will run. Climb the ladder and you will see a beating heart with chains on it. This is the heart of the statue of happiness.

Liberty City Stories Ringtones
When you are selecting ringtones for your cell phone, some of the "modern" ringtones are actually songs from Grand Theft Auto: Liberty City Stories.