Highest resolution for steaming radio on I-Phone

Okay, I don't have a computer right now and found a Wadia 170i for $100. I bought the Wadia with the intent of buying Pandora one and streaming audio at 192kbps, but now I'm confused about whether or not I will be able to do that. From what I'm reading on the net, it seems you can only stream at this higher rate through a computer? I don't know anything about computers and mac airport this or that, so if you start talking computers to me, dumb it waaay down.

Question number two: are there other sites that would work solely on the I-phone at a higher rate, like spotify or any others? I have only used regular pandora thus far.