This error happens because you try to play a game in the web browser directly when running INDEX.HTML. Modern browsers have a security system that prevents local files from trying to capture information from other sites via AJAX, but you can disable this security (CROSS-ORIGIN). The...
Hmm, I'm afraid this is going a bit over my head. When you deploy a game as a standalone android app, does it still use a browser to run?
I know most apps use the Android/Data file path to create a folder for their files, which I have seen suggested as to where the save files are stored, but it doesn't seem to be creating them there. Would having the app in Canvas vs WebGL have any effect on this?
I downloaded a game that the system saved the data in a public or private folder without using localStorage, but the creator did it directly in the Rpg Maker files instead of using Plugins to modify it.