AndChat is a free IRC app for Android that works astonishingly well. You can save multiple connections to connect to different servers, save credentials to speed up the IDENTIFY process, chat logging, and it gives you a nice clean chat interface while talking with people. It even features a widescreen mode!
The free product is full featured, and there is a ~$3.25 donate version of AndChat available, or you can donate your own amount of your own at