I'm an iOS developer. What would people want in an ecodriving app?
 

So I just discovered the GoPoint OBD2 cable for iPhone a few days ago. And it got me to thinking...

If someone were to make the ultimate ecodriving instrument, what would it do? Obviously you could make a ScanGauge-type device pretty easily, but what would people really want? After all, the iPhone is a lot more capable: it has GPS, an internet connection, an accelerometer, a compass, and of course OBD2.

So you could, for instance, have a "¢/mi" meter that looks up prices on GasBuddy. You could query NOAA for wind-speed. And you could make any gauge you want -- how about a "drag gauge" that you enter your car's CdA and Crr? Or a "hill-climb gauge" that shows how far you could coast up a hill (I'm always terrible at that).

I have a little demo app that I could develop further, if there's sufficient interest.

So let your imagination run wild! Usual brainstorm rules apply, please.

A pulse-and-glide gauge of some sort would be very cool. Hit the "start cycle" button as you start the glide. Coast down to your minimum speed, then bump-start and accelerate back up to your initial speed. Have it calculate the MPG over the duration of one glide / pulse cycle, to give instant feedback. This would be better than the instantaneous display, which would just show infinite mpg on the glide then low MPG on the pulse.

Instead of a "speed warning", have an "acceleration warning", so when you are frustrated in traffic and decide to bolt around someone you get an annoying alarm to remind you to ease up on the loud pedal.

like you said a scan gauge app, that's it. Maybe something with an obd2 interface capabilities

...come up with some way to interrogate, integrate, and display a realtime Brake Specific Fuel Consumption (BSFC) graph for the engine.

Also consider spending some time here, ecomodding and hypermiling your own car, so you understand the "business" side of things and are not self-siloed into a limited role when you start.

Ah, looks like no car, how were you going to test?

There's already a few OBD2 apps.
Take a look at what they do, and what you could add.

A simpler set-up would probably sell better to the average Joe.
An extensive hypermiling feature set will sell better to the ecodriver's niche-market - but we're below the 1%-ers ;)

The internet connection isn't always on or working though.
Don't fall into the developer's trap that the 'net always needs to be working for the app to function properly ;)


Must haves :
- logging
- high frequency OBD polling, i.e. realistic measurements updates.
- % time and distance idling
- % time and distance in which gear


Not everybody has those figures.
Even a lot of us don't even have them.
CdA is relatively easy to find, but Crr ?

You could maybe built a feature that grabs the required time/speed data and calculates the drag ?

You'd need to have the topography of the road ahead, actual vehicle weight, RR, ... this would get complicated very quickly.

It would be nice, if it had a mode where it shows the BSFC-chart on the screen, and a cursor on top of it, that moves around and shows you where you are at rpm and load-wise.

@dennyt: Oooh, I like it. An "average mpg since last pushed" button. It seems like that would accomplish what you want, no?

@War_Wagon: Nice. Throttle position would work too, it seems.

@Old_Tele_man: BSFC maps would be hard, since you can't measure the torque output directly. You can interrogate the RPM readily, so the X-axis is nailed down. Theoretically there's some monotonic function that relates throttle position to torque, and throttle position you can get.

@dcb: In my intro post I noted that I have access to an OBD2-capable car (a 1995, no less)

BSFC mapping would be my biggest interest by far.