After working successfully for 18 months, I now get many drops in my internal GPS. Even sitting outside in the garden with a perfect view of the sky, GPS Status and Google Maps give perfect results, but Skydemon is 'Waiting for location' more than half of the time. This problem started about 6 weeks ago. 

Using SD 3.0.7.19226 on Android 4.4.4

I made the first test flight today. GNS2000 is the bluetooth GPS receiver, Nexus7 is the slave running SD.
I checked 'Enable Mock GPS Provider' on.
GPS reception and position is good, but no groundspeed or course over ground. So on the SD screen, my position is OK but no speed vector shows up and it looks like I am flying backwards or sideways.

I use Bluetooth GPS app as the gobetween.