Dude, iPhones are getting less expensive.
They have a corrisponding app for Chords as well

HOWEVER :

After finding and buying that app, I found an even better one.

Guitar Toolkit. $9.99... May have to buy this one too. Will just relace the scale one i got though
http://www.agilepartners.com/apps/guitartoolkit/

The folks who make Guitar Toolkit aslo have a very cool app for Tabs
http://www.agilepartners.com/apps/tabtoolkit/