Shytorque
I don't think it is a wing masking issue, some above have indicated that it might be an issue with the iPad multi tasking.
I think the next move is to shut the iPad down before I use the skydemon and only open the skydemon app.
The other thing I need to look as is the skydemon reliability compared to the Jepp FD, I will run one on the iPad and the other on the iPad mini, if it is a GPS signal issue they shoud both have the same problems.