How to Get Halo on iPod Touch or iPhone
Finally Halo comes out on the iPod Touch and iPhone!! You must have a jailbroken iPod Touch or iPhone and have Cydia! Also upgrade to firmware 2.0 or higher through iTunes!
Use the source: repo.halo4iphone.com
Then download and install all applications from the source. This will let you play XBOX 360 Halo 3 on your cracked Apple iPhone.