Just wanted to share this.
http://usealice.org
Simply, it is an IRC web client that doesn't suck. However, it has a neat feature that keeps you logged in to IRC while you are away for up to two days (more if you decide to purchase a subscription, which is completely optional). I have used this client quite a lot, and find it quite useful since it handles the client being disconnected well, which is good for when I am using IRC on my phone, since I am with the world's shittest carrier. It also looks good on phones on the like, meanwhile Mibbit and CGI:IRC requires lots of pinching, tapping and groping to use. The site it is on has some screenshots of how it looks on several devices. It's also nice to be able to seamlessly switch between devices, should you need to.
Also, some things to note:
-You need to have an invite code, which can be obtained from the page linked above.
-This client only works with browsers with good HTML5 support. Basically, any modern browser.
-If you use Google Chrome, you can get desktop notifications. I don't know how to do that, though.