there is a new rev app which has come out in the states, basically it connects to your ecu and reads all sorts of shit up on your iphone screen , read below......... By itself, the app can measure 360-degree acceleration using the iPhoneâ??s built-in accelerometer, and a GPS Track feature which will map out the track youâ??re driving on after one lap. To use this app to its full potential, however, you will need to buy a piece of hardware to connect to your OBDII port in all 1996 or newer cars. We used the excellent new PLX Kiwi Wifi. This tiny $150 device connects directly to your OBD