There are a large amount of secrets hidden in Grand Theft Auto IV. Some are simple passwords, and some are Eater Eggs, and a list of them can be found below.
Passwords
Cell Phone Passwords
To use theses, pull up your cell phone in the game and dial the number.
| Number | Effect |
|---|---|
| 468-555-0100 | Change the weather |
| 486-555-0150 | Get a different selection of weapons |
| 486-555-0100 | Get a selection of weapons |
| 267-555-0150 | Raise wanted level |
| 267-555-0100 | Remove wanted level |
| 362-555-0100 | Restore armour |
| 482-555-0100 | Restore health |
| 948-555-0100 | Song information |
| 227-555-0142 | Spawn a Cognoscenti |
| 227-555-0175 | Spawn a Comet |
| 938-555-0100 | Spawn a Jetmax |
| 625-555-0150 | Spawn a Sanchez |
| 227-555-0168 | Spawn a SuperGT |
| 227-555-0147 | Spawn a Turismo |
| 359-555-0100 | Spawn an Annihilator |
| 227-555-0100 | Spawn an FIB Buffalo |
| 625-555-0100 | Spawn an NRG-900 |
Computer Passwords
To enter these, enter them in the URL on an in-game computer.
| URL | Effect |
|---|---|
| www.whattheydonotwantyoutoknow.com | Marks all weapon, health, armor, vehicle, pigeon, ramp/stunt, and entertainment locations on the map. |
Unlockables
Unlockables
| Unlockable | How to unlock |
|---|---|
| Annihilator Helicopter | Kill all 200 flying rats. |
| Rastah Color Huntley SUV | Complete 10 Package Delivery missions |
| Unlimited Ammo | Achieve 100% game completion. |
| Statue of Happiness T-Shirt | Enter the secret room of the Statue of Happiness. When you exit, you will be wearing a Statue of Happiness T-Shirt. |
| GTA III Clothes | On the mission "The Holland Play", if you kill Playboy X, you will receive his apartment. In his wardrobe, you will find Claude's (GTA III's protagonist) Leather Jacket and Trousers. |
Friendship Bonuses
| Name | Effect | How to unlock |
|---|---|---|
| Boom? | Call Packie to make you a car bomb. | Gain 75% friendship with Packie. |
| Chopper Ride | Call Brucie to pick you up in a helicopter. | Gain 70% friendship with Brucie. |
| Cheap Weapons | Buy weapons cheaper from Little Jacob. | Gain 60% friendship with Little Jacob. |
| Back Up | A car of gang members are sent out to help you | Gain 60% friendship with Dwayne. |
| Free Ride | Have a Taxi sent for you. | Gain 60% friendship with Roman. |
Dating Bonuses
| Name | Effect | How to unlock |
|---|---|---|
| 50% off | Get 50% of all clothes at clothes stores. | Get 80% relationship status with Alex. |
| Health Boost | Call to get a health boost. | Get 80% relationship status with Carmen |
| -3 Stars | Call to get 3 stars taken off your wanted level. | Get 80% relationship status with Kiki. |
Easter eggs
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.