OBDZero reads, displays and stores data from the iMiev, CZero og iOn electric cars. This data such as speed and electricity use is available on the cars CAN computer network via a Bluetooth dongle attached to the cars OBD port. The data is presented in 7 different screens. An 8th screens logs messages between the app, the OBD dongle and the car. Two screens are intended for use while driving. One of these, the WATTS screens, shows the cars average watts, speed and watt-hours per km. The other screen, DRIVE, updates the distance to the next charging station, the difference between the remaining range and the distance to the station, and suggests a speed to the station.
The app saves data in semicolon separated text files, either in the phones internal RAM or on an SD Card depending on how the phone is set up. OBDZero was developed on an older phone running Android 4.3 with an INTEY OBDII and Vgate Scan, both inexpensive Bluetooth dongles. It also runs on the more expensive OBDLink LX dongle with recent firmware. It has been tested on a newer phone running Android 7.0. The app does not exchange data with the Internet and it does not use GPS.
There is a user manual which you can request by email.
The app still has bugs so please be patient with it and I take no responsibility for any consequences of its use.
Acknowledgements and references:
Much of the code for OBDZero comes from Blueterm by pymasde.es.
The commands to the Bluetooth dongle were found in ELM327DSH.pdf from www.elmelectronics.com
The interpretations of the CAN PIDs for speed, voltage and current etc. were found on http://myimiev.com/forum/ posted by jjlink, garygid, priusfan, plaes, dax, cristi, and kiev.
Special thanks to Anders Fane and Allan Korup for their advice on electric car and CAN technology.