title: How to make an iOS asset bundle?
body: <p>I saw a custom asset bundle in an iOS project I evaluated, so at least I know it's possible.</p>
  
  <p>My issue is that I'm using a CATiledLayer with about 22,000 tiles for a given image and it takes a very long time to compile (half an hour clean build, 5-10 minutes for regular build). So, I want to take all of the images and make a custom bundle to make it portable and hopefully not recompile into the app bundle each time.</p>
  
  <p>How do I go about this? I checked the docs, but didn't see an explanation on how to actually create the bundle. </p>