retina.js

What do you like best?

It is a really simple solution to implement. You just include the .js file and voilГ , your website automagically supports Retina pixel density. You don't have to fiddle with CSS or come out with your custom javascript; it just works... and moreover it's free! Sure, you'll appreciate the difference only when seeing your webpage on an Apple display, but the difference is huge and these great devices deserve special care.

What do you dislike?

The only issue is that with upmarket smartphones which have Retina density displays, some bandwidth is lost since the users get to download the same image twice or thrice, but it's a compromise that is more and more rendered painless by the increasing data plans most companies offer.

Recommendations to others considering the product:

There are a few alternatives out there but Retina.JS was the first one and still goes strong so it may very well be your first choice to add hassle-free Retina support in your websites.

What problems are you solving with the product? What benefits have you realized?

I can now design websites that look pixel perfect and razor sharp on the best displays on the market, without much hassle.