Website Codes
Use a computer at one of the local businesses and log onto various websites to unlock secrets and codes. Type in "www.littlelacysurprisepageant.com" to automatically raise the wanted level. Type in "www.love-meet.net" to make friendships and potential lovers. Type in "www.whattheydonotwantyoutoknow.com" to reveal map locations of items like weapons and health. Customize the cell phone by going to "www. vipluxuryringtones.com" and choosing a new theme or ring tone.
Phone Cheats
The cell phone is a huge part of "Grant Theft Auto IV," and dialing certain numbers will help players earn extra items and weapons. Dial "227-555-0168" to make a SuperGT appear. Dial "482-555-0100" to restore health. Dial "267-555-0100" to remove the wanted level. Dial "468-555-0100" to change the weather; repeat to achieve ideal conditions. Dial "486-555-0100" to get a selection of weapons.
Friendship Cheats
Become friends with specific characters to unlock cheats to use throughout the game. Become friends with Brucie to get free helicopter rides anytime. Become friends with Kiki to get the police away from you. Become friends with Dwayne to have gang members for protection, and being friends with Jacob will let you purchase the cheapest weapons.
Money
Use a glitch in the game to build up a money supply. Steal a collection of cars and use them to surround and block off an ATM. When a pedestrian approaches the machine, attack him until he is dead and you can pick up the money. Wait for the ambulance to arrive, then run away for moment. Return, and the money will reappear. Repeat this process to build up the bank account.
Free T-Shirt
Get a free souvenir by visiting the Statue of Liberty. Head inside the actual statue and walk up to the second floor. Instead of opening the door, use the analog stick to guide the player straight through the door. The player will disappear and after a moment, he will reappear with an official Statue of Liberty T-shirt on. Repeat this cheat at any point in the game.