Thanks for the information! So if you want to display a dynamic image containing real-time information when the recipient opens the email, it will still work since Gmail only caches the image for a short time, right?
Depends what you want to base the dynamic information on. If you want it to be time based, I.e the current t stock price then that should still be possible. But say you want it to be based on user location, like the weather in the users location then that won't work because you won't have the users original IP address so you won't be able to roughly detect their location.
