So I've never made a game before besides a basic 4:3 aspect ratio flapper, so bare with me. Recently I had this wild idea that I wanted to make this complected (for a 2d) game in cca. Unfortunately I'm stumped. At first I decided it's smart to program my game in a 16:9 aspect ratio, but then I thought about it... The iPad and Nexus 9 work in a 4:3 aspect ratio. How would one make a game (like a flapper) scale to both aspect ratios?
Edit: If it helps at all, I will be using JS... Primarily the Pixi.js library.