Something to try if you are experiencing connection to drone issues with android
My connection issues were due to my wireless router. The request for the dji token was being blocked. It appears to be a problem with android only because the ipad connected no problems
The problem was fixed by
- turn on mobile internet on phone (only use wireless usually)
- creating a wireless hot spot on phone
- disconnect android tablet from wireless network
- connect tablet to phone hot spot
- fire controller etc up in sequence
- allow ctrl+dji to get the dji token
- shut it all down
- put all the wireless settings back to original
now I have the initial token all works fine through the wireless network
hope this helps someone else