Normal flight this afternoon. Charged batteries and on second flight motors start and I can fly manually but no telemetry - picture, battery condition etc. Telemetry says not connected - no satellites shown but the machine holds station in a breeze and flies normally. Any ideas?

Have you ruled out the cord between RC and mobile device?

Yes, tried another cable with same outcome. On one attempt the camera view came through and I could move it up and down. Nothing else works on screen. Thanks for your interest.

Contacts on camera mounting plate nice and shiny? Are all of the prongs in the female side of the mount straight and none bent?
Is this an X3 or X5? I use both and downgraded fw because it made the X5 virtually useless.
See: http://forum.dji.com/thread-52361-1-1.html
But I never had the problem you describe.
Do you have another monitor to try? Another smart phone or tablet?

Here's another possible fix:

Refresh the video link with the buttons combination:

Press the C1 + C2 + Trigger (photo) buttons and keep them pressed and TURN OFF the controller.
By still keeping pressed the C1 + C2 + Trigger (photo) buttons TURN ON the controller.

Thanks Aeromirage. I'll try another tablet later and your other suggestions.