We've just posted a public beta of SkyDemon 3.5 on our Android page, which includes rainfall imagery. Please give it a try and let us know here how you get on.
http://www.skydemon.aero/start/beta.aspx

thanks for that..... have tried it in flying mode.... nice!...... one observation - if you have both terrain safe and weather turned on, rain seem to be taking preference to mountains - i.e. what was a red mountain now becomes a pale blue cloud ..... so I might try to fly through it.  I think terrain should probably take precedence to rain.

Is there any way to tell when the rainfall data was last updated?  If I was out flying for a couple of hours, I may or may not occasionally pick up a 3G signal, and I'm not clear if I'm looking at a forecast from a couple of hours ago, or from 10 minutes ago.

Finally - counter to MikeTwoOne's view - I really like the time selector - really easy to see selected time and change it without messing around with hour and minute selectors etc