If you don't mind spending about $2 there is an Ipad application called 'Travel Budget Tracker' but I think you may have to buy it through the Itunes shop within the Itunes applicaion that I'm assuming your Ipad has.
Cheers
Jon
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Home is where we hang our hats - Home now in Yamba NSW
Aa very handy app I used for ages is "Road Trip". It keeps track of all your vehicle expenses, calculates fuel usage, repairs and services, and reminds you when service/rego etc is coming due.
It also has a section for tracking road trip expenses
I think it only cost $1 or so and worth having a look at. I used it on my iPhone as I always had the phone when refueling etc, but it works on my iPad too
David