Don't get no better...

I have a Scangauge II. I tops out at 9999 MPG. Either real time or average. (I also display RPM and engine temp). One can display 4 of 16 (or more) possibilities right on the gauge. No cellphone or tablet/PC required. I had the microcode customized so I can leave it plugged in 24/7. IF anyone orders one for a Prius, (or any other hybrid most likely) order from the factory and specify your Prius Prime or otherwise. If you buy from a dealer, it probably won't know when to turn off... or alternatively turn off any time you are in EV mode. I exchanged probably 3 units with them +my original 'til we got the coding right. Now I have had it connected for several months with no "stay ons" when it should turn off or "turn offs" when in EV mode or HV/battery mode. They sent me programs to try and I sent them the hex results. 3rd one was the charm!

 

Across the sea to Bristol UK ?