To go along with the sweeping changes Microsoft implimented on Xbox Live yesterday, the company has released an iOS companion app that allows you to keep track of your friends, send messages, update your profile and gaze longingly at your gamerscore while you count the hours until you can return to your 360. The Xbox Live app is free. Here's the app store link.
If you're a Windows 7 Phone user, there's love for you, too. The Xbox Companion for Windows Phone 7 is live as of yesterday, and that application lets you do everything the iPhone version does, but also lets you control content from your Windows phone. Amazing...and also, free.
Check out our Xbox Live dashboard preview for an overview of everything new on your system.