How to get better quality web render?

[sicher]

On desktop you will get high dpi proper if you enable it in the project settings (high_dpi).

It is important though to understand that enabling this will create a high dpi buffer for rendering. All measurements stay the same. Any content that is rendered at 1x scale will look the same. But if you import high res images and scale them to 0.5x they will be high dpi on screen.

Check out:

What is a proper way to handle textures on universal app for high and low res devices

Is this possible to make the one scene with the same atlas which will perfectly looks on face book app (800x600 app size) and iPad pro (2732x2048 screen size). Do i need to use just one high res texture and the engine will downscale it or maybe there is a better way like 2 different atlases for high and low res? What i think, correct me if i wrong, that downscale is not good because low res devices has less video memory and 2732x2048 textures could take all memory. Thanks.

If you do this right you will get crisp rendering on desktop. For HTML5, I am unsure how the support looks. @sven probably knows more.