<p>@GMTplus7 That has more to do with resolution than screen size. More pixels means you can divide up the screen more without losing quality. 15 inch macbook pro has retina, 13 inch macbook air doesn’t. A 100% increase in pixel density (with no screen size change) will do much more than a 33% increase in screen size (with no resolution change). FWIW I use a 13 inch 2880x1620 and it is much easier to read two things open at once than my old 1920x1080 15 inch. </p>
<p>But retina adds another $300 (for 13 inch) to $1000 (for 15 inch) compared to 13 inch air. Hard to say if it’s worth it for that much. OP should go to an apple store and try them for herself.</p>