Fade particle opacity according to distance from camera?

Hi All
I’m working on iOS (base pro, though not iOS pro for the time being) - I want to ramp the opacity of particles down to zero as they approach camera. Is there a simple way to do this?
It appears that soft particles don’t work on iOS - - so this would be a pretty good workaround for my needs.

Thank you for posting the link.
This appears to work great (after ferreting out a phantom typo on my part. :wink: