Best practices - Saving Player Settings across platform change

I apologize if this was already asked, but I can't find the question asked.

I am looking for best practices for working with a game that builds across iOS and Android. I set the platform to iOS, entered my Player Settings (icons and images), built that, then changed the platform to Android. Once switching back to iOS, my player settings were gone.

What are the best practices for being able to update a single game for multiple platforms without uploading the exact same images every time you go to see it on another platform?

Thank you in advance!