If I use the weather function when flying nothing is showing on the map(arrows)?

While in flight mode, click the skydemon globe in the upper left, click the weather menue item (second from bottom), find the "turn on weather overlay while"

I'm using the actual iphone-version, iirc, this feature is new/changed location

And is there a way to show rainfall a little transparent so one can still see the map information underneath?

There is no way to increase or decrease the opacity of the rainfall layer. It is not designed for tactical use in flight, and should not be used for that purpose.

In the past I had a very useful wind barb / arrow on the left bottom side on the screen. I cannot find a menu to see it again....in google play it is still to see in the sample screenshot. I use Android 3.7.1.28802. For me it is not so helpful in navigation before every flight to switch on weather overlays. And to search the map where is a wind barb...
I am looking forward for a tipp to get  the wind barb again at the left bottom side! Claus

+x

flieger-claus - 5/7/2017 2:09:51 PM

In the past I had a very useful wind barb / arrow on the left bottom side on the screen. I cannot find a menu to see it again....in google play it is still to see in the sample screenshot. I use Android 3.7.1.28802. For me it is not so helpful in navigation before every flight to switch on weather overlays. And to search the map where is a wind barb...
I am looking forward for a tipp to get  the wind barb again at the left bottom side! Claus

Offline?

Claus, it sounds like you've probably just turned off the wind instrument. In flight, Setup -> Instruments.