This is a much needed feature, it would greatly increase the connectivity reliability and let users check in and operate when away from the immediate home wifi.
To be clear for others, what Astrobert is asking isn't a technical issue and has nothing to do with the ASIAir or it's networking ability/functionality today. It's an entirely different approach to the device connectivity.
Liken it to how a NEST thermostat, Hue lights, or Apple Home devices are able to control stuff in your home while you are on your phone anywhere in the world. it's publicly exposing the device to the network and it's not small security measure and requires some way to broker that.
Astrobert's VPN method works great but it's a localized version, good for just one person and one device. there are "hacks" so to say that you can expose the ASIAir to your router, use port forwarding and tunnel into your network using a VPN. pretty much only able to be configured & usable by strongly skilled IT people.
I think the better solution would be to just step into the full remote services option. but as franco suggested, this requires ZWO to establish a broker and additional platform to bridge public networks with private networks and not create a major hacking exposure situation. it's very doable, but it definitely is a project for ZWO to take on. One I think would be great, although I'm not sure how many of their custom base would care or even use it so unless there is broad demand they likely won't prioritize it anytime soon.
Astrobert - you might want to google some of the crafty options that are out there to accomplish this for yourself, I think there's even a post lingering around this forum that describes how one person did it.