One other update ... It seems that on our test T-Mobile phone that if we turn on Airplane mode (resetting the LTE connection) and then visit the
http://ipv6-test.com/ link, the "Fallback" test fails with a red "No".
Then, when launching iCam Pro, we get a Broker Connection Error.
Then, (and this is where things get strange) if we launch our iSpy Cameras or iSpy Cameras Free app (
http://skjm.com/ispy/) the public IP cameras will eventually start to connect, which is not expected if there was no IPv4 connectivity.
Then, if we go back to the
http://ipv6-test.com/ link, the "Fallback" test fails with a passes with a green "to IPv4 in 1 second" and iCam Pro works.
We are still looking into WHY this is the case, but am wondering if this same strange work-around works for you.
If we had to guess, we think it has something to do with T-Mobile's network, and how they're handling the IPv6-to-IPv4 fallback / translation.