This might be of interest to a few people, I haven't got my car yet but I'm thinking ahead to when it arrives and will probably log into Fuelly.com to register MPG and fuel costs. There is a mobile site but no app for smartphones.
It's an American site (with no Evoques on there that I can see) but you can set it to UK Units and £[/code]. I originally noticed it being used by Audi owners on another forum I use as you can add a Fuelly banner to your forum signature.
Here's an example of a from a RR owner:
http://www.fuelly.com/driver/ntan/range-rover
And some info on using the site if you are in the UK:
http://www.fuelly.com/faq/21/Fuelly-in-the-UK