Good idea. I had already added my 'free' ESXi license to the installation. But on a whim I tried swapping from the free licensed-mode to evaluation mode (as I still have 60 days to evaluate), interesting to note that this change allows me to administer VMs via the iOS vSphere client.
So...is it possible to take full advantage of the iOS vSphere client + vCMA with just a 'free' ESXi license? It seems the answer is no.
Bummer.