While I was working on a customer project with a share function that should include an image, I was curious about how the image would turn out for the different sizes on web and mobile devices. This document includes three sizes: Web, iOS (iPhone 7@1x - 375x667), and Android (MDPI - 360x640).
Everything is made out of Symbols (they're also organized for your convenience) and resize options have been set, so you can resize the layers to create other sizes for other devices (tablets etc.). It also includes the new icons Facebook introduced with their new update. Enjoy!