Live Preview Options by Webyze

One of the easiest apps I've ever used -- takes a bit of time getting used to the learning curve but the conditional logic is where it really shines. You can have how many ever permutations and combinations of a product.

Please watch the YouTube videos in the help section and you'll understand how well this has been built.

One feature I might request is the ability to create template option fields so you can apply to other products. Instead of manually adding it every time.

Otherwise I'm in love with this product -- never seen anything like it on Shopify and shocked that it isn't built in.