Probably a basic question to the experts in this
Example:
I have image 2000x1500px @ 556kb - a set of pictures of that size causes iOS devices to not load the page (considering there are many pictures) due to cache levels I'm guessing.
If I create two of the same files one at 2000x1500 and other at 800x450 with a much lower weight due to smaller dimension - which would be intended for mobile devices only.
How would I address that in CSS or whatever is the right method to go about this?