Collection Repeat - Image Item (recommended size in kb)


Hi Guys,

I wonder what could be recommended image size (kb) of the item inside a list so the collection-repeat handle all scrolling smoothly ?

What item is 1 large image and I am curious what others, if they even do some image compression and optimisation.

e.g. even if I use and tell this cloud service (this one handles images for me) to size image for me with iPhone screen size, with set DPR to 1.5, it still have 350 - 400kb.,h_221,dpr_1.5,c_fill,fl_progressive/v1415207651/beaches/800000009.png

So its more what is practical and still maintain good quality photos.