This is a really nice application – best of it’s kind, in fact – it’s aimed for hardcore Xbox 360 and iPhone users. 360 Live is good looking iPhone and iPod Touch application that retrieves your friends, Xbox Live stats such as their gamerscore, online status, gamer pictures, avatars, latest games, achievements, send/receive messages and much more.

Main Features:

• Sign in securely using your Xbox Live credentials. 360 Live automatically retrieves your friends.
• Complete Gamertags management. Add, remove, accept or reject pending requests.
• An organized Friends List. Grouped by status (Online, Offline, etc.)
• Gamer Profile and details including gamerscore, bio, location, country, gamercard, avatar, etc.
• Check your friends complete games history.
• Compare locked and unlocked achievements per game and gamertag.
• Send and receive messages. You can even send messages to multiple recipients!
• Gamercard coverflow style carrousel on landscape mode!

360 Live, unfortunately, isn’t free but it’s rumored Microsoft will insist it be free and make this app free. – 360 Live [iTunes Link] is $1.99USD and you can get it in the AppStore [iTunes Link]

- source: get360live.com

P.S. While you’re at it, check out xbox360-hacks.com