I'm digging Fuelly. The only thing I would love to see beyond what's here is a "Remind me in x miles" feature to the note system.
Oil changes would be the obvious example: I change my oil, add a note to Fuelly in the usual way, but there'd be an optional field at the bottom to choose a mileage interval, and one to specify a brief note. The first time I fuel up after the interval has been reached, it triggers an message containing the note (e.g. "Hey! Change your oil!") to my registered email address.
Could be very useful, especially since we're entering the pertinent mileage data anyway. Oil changes, air filters, tranny/diff fluid, plugs, tyre rotation, etc etc..
Programmatically it would seem in my simple brain to be a few extra columns on the user's profile and a routine at submit time to check it.
That is my suggestion. Cos proper maintenance is vital to good fuel consumption!
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