Currently http://BlockStreet.info gets data from:

Bitfinex
Bitstamp
BTC-e
Bter
Cryptsy
Kraken

MintPal is in the next push this week.  Who should I add next to the app?  Vote for your top 5.

If they're not listed above, please feel free to recommend in the comments.  Thanks 

(Have you checked us out yet?  http://blockstreet.info )