I just bought an ELM OBD II Bluetooth adapter on Ebay for less than $15 and I'm going to use this Android app
on my phone to check my vehicle codes and reset fault indicators as I see fit. I'll report back how well it works once I've tried it and I'm hoping that it will save me needless expense by doing it myself. It could also be useful when you're towing to keep track of vehicle operating parameters.
It appears to be a crap shoot whether it will work with your particular phone model, OBD adapter and vehicle combo but it's promising enough to me to give it a $15 dice roll.