Help identifying a bird

Any colours? Song? Behaviour could be grey wagtail catching flies? But could also be one of many others doing the same!

Thanks for your reply. It was very small, it kept flying straight up a metre or so and spinning down to land a few steps away, then repeated. Colour no dark markings...

Meadow Pipit is a possibility. Their display flight involves them ascending vertically and then "parachuting" back to the ground. They usually go a bit higher than a couple of metres though. Fairly nondescript little brown birds with brown streaked back and pale streaked breast.