Whenever I make screenshots for my apps, I'm always forced to resize them to specific requirements set by Apple for the various devices. At the end of the day, the pictures that look really good in Adobe Illustrator look all stretched out and distorted because of the resizing. Is there something I can do to fix this problem?
Your problem seems to be that you don't keep the aspect ratio of your images. Let's say you have a quadratic image
and the device you are using is say w:h=1:2, then, when you simply force your image into this format, you get
To keep the image unstretched, you have two possibilities. First, you keep the aspect ration during resizing and add a margin
Or you take not all of your image. This can be done by resizing your image (keeping the aspect ratio) to the longest side and cropping it then to the desired dimension: