Comment by londons_explore

That's often out of date, and the UI is pretty buggy (at least on iOS).

There's also 'Gaspy' which is really a NZ app that was very popular in NZ (I used to live there) where people submit and confirm prices, but in the UK there aren't that many users (hasn't got critical mass), so there are often no prices or things are very out-of-date.

I’ve used that app for some time but unfortunately it relies on user reporting, and the prices can be days or weeks out of date.

The AA also show prices through their app.