This app is intended for the non-plug-in version of the 3rd generation Prius (ZVW3#, 2009-2015, NIMH Batteries). It may (partly) work with other Prius versions.
The app can be used to show detailed information about the car like general car/engin information, Battery Status information, Battery Block Voltages, Engine operation,.....
I tested the app with an ELM327 bluetooth dongle plugged in the ODB2 port (under the steering wheel). These devices can be bought for less than 10 euro/dollar e.g. from China.
Rather than dump a lot of parameters, I tried to have the app provide parameter groupings/graphs of parameters that make sense to watch together.
If you think certain extensions would be useful please provide motivation why/what parameters would be useful and I will see what I can do. You can send your request to gvli@telfort.