Originally posted by mattt My experience (and I've shot with ImageSync a fair bit) there appears to be cellular interference affecting the signal of BT/WiFi. I have found success disabling the Cellular service when i need to connect to my camera(s). I believe the issue is an Apple design flaw not related to ImageSync.
I think that may be related to the setting to use cellular if wifi internet access is not working. See if turning off WiFi Assist helps. On my iPhone I have to disable autoconnect on my main WiFi since I am unable to keep connected to my KP if I do not turn this off. I do not have problems with losing connection or not connecting with the Wifi and Cellular enabled. My Wifi Assist is turned on. (This is with the KP)