I understand how 1x, 2x and 3x image resolutions work but I'm unsure how I go about choosing the right size/resolution for custom images in general. Imagine that we have a simple layout like the following:
Now it is up to me to create the image (in Photoshop for example) for that UIImageView. What size and resolution should the highest quality version be? Do I just use the highest screen resolution of the iOS devices that are currently available as my guide?