A while back I purchased a Bluetooth OBD II reader, mainly to read and clear the codes when the gas filler cap wasn't tightened enough on our cars. The one I got is the OBDLinkMX (obdlink.com).
Among other features, the Android app also includes a cool dashboard function with the ability to display multiple screens of digital or analog gauge faces of any of the OBD II data available (and there is a lot), as well as some info from whatever phone or tablet the app is running on, like acceleration. It also has a dashcam feature.
I fabbed up a mount and hook and looped to the dash, and hook and looped a 10" tablet to the mount. I set up one screen with Vehicle speed, Trip Distance, Total Fuel Economy, Fuel Rate, Volts, and Instant Fuel Economy digital gauges. We used it on last week's trip up to Lake Almanor and back and it was really nice to be able to see those things. I used the speed gauge more than the dash speedo. The gauge sizes are adjustable, and you could set up multiple screens to swipe between.
As yet unexperimented with is the "Heads Up" display function, which mirror images the screen. Presumably, you would then place the tablet on the dash such that it would be reflected by the windshield.
I also run the Bluetooth apps for the Victron battery monitor and the Renogy MPPT solar charger on the same tablet.
It worked so well that I'm considering adding at least one more 10" tablet to the dash for full-time Waze and/or Off-Line Maps and Navigation while in motion.
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Linear Mode
