I’ve been playing with Meteox and it’s pretty cool. It gives you a composite weather radar for most of Europe based on inputs from national weather authorities.
It was useful last week when there were complicated weather systems over the UK and I had to get to Cardiff and then to France. I could see where the fronts and troughs were and plan my routes and timings accordingly.
It’s not as good as an in-plane weather radar or the satellite download weather you get in US Cirrus planes but it’s pretty useful.