Bluetooth ELM 327 Scanner OBDII PC Car Diagnostic
Got it from Amazon. The device plugs into the OBD2 port and spits out any OBD2 info that your vehicle has the ability to read, It does not matter what car as long as it is OBD2. I have used it in 3 different cars and they all work.
Now, as far as iPad goes, you are on your own. I don't support closed programming, so I don't know for sure, but I have read that apple will not let OBD2 stack be read because they won't pay the iPad mafia fees. Android, on the other hand, has hundreds of apps that will work with this device (many free) and I have a Windows Mobile device that also has hundreds of apps (also free) that will work.