No surprise to any of y'all: screens come in a whole lot of different sizes and pixel densities these days. The technology behind dealing with that is catching up. For example, responsive images. So, we need software to help us generate those many versions of images we need.
Thankfully, all the most popular design software is starting to accommodate that need. Adobe Photoshop, Adobe Illustrator, Sketch, and Affinity Design all have pretty solid workflows for doing just that. I cover all those in this post over on the Media Temple blog.