There are ways to connect to IRC on from your iPhone.
Commerical App
rooms
If you’re looking for a commercial, easy-to-use IRC client with rich GUI, Rooms is available from the App Store.
Free App
ircm
If you’re just looking to get connected and know your way around IRC already, the quick, free way to
get onto IRC is to install iRCm, which can be found in Cydia on a jailbroken phone.
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iPhone doesn’t come with any chat programs, like AIM (AOL Instant Messenger), Yahoo Messenger, or MSN Messenger. But there are MSN like instant messaging tools like MSN on iPhone. The one I prefer to use is eBuddy, eBuddy allows you to sign in to multiple accounts like MSN, Yahoo!, AIM, ICQ, Google Talk and Facebook buddies etc.
The official page is at http://www.ebuddy.com/iphone/
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