iOS for iPad does not support for multitasking, that’s the fact you have to know. So, you just can’t listen Internet radio while you are running another program on iPad. However, you can listen to the radio while work something on your iPad. Don’t worry you don’t need to install any extra apps and/or jailbreak your iPad.
Find the radio-only stream, work with your Safari and start to run another application. That’s it.
Here is the example, “FairerPlatform cites Soma FM, a San Francisco-based, user-supported internet radio station. Their music is available in the pls multimedia playlist format, which the iPad’s Safari plays without a hitch. Once you’ve started the stream, you can do any other work you need to and the stream plays on in the background.”
We do have another example to listen radio in background on iPad.
If you had an account on TWIT, insert the address http://live.twit.tv/ in your Safari browser and tap on “Live Audio Stream“. Now you can enjoy the radio broadcasting while working with the other program on your iPad.
The unofficial Apple Webblog admits that this is a nice trick to enjoy radio broadcasting on iPad also becomes the alternative before having native application for radio streaming.