What is the difference between Zepto and jQuery 2?

Question

There are those two similar projects:

Zepto.js

Zepto is a minimalist JavaScript library for modern browsers with a largely jQuery-compatible API

Answer 1

jquery 2 is ~30kb and zepto is ~10kb when both are gzipped and minified. Non gzipped but minified, jquery 2 is ~80kb and zepto is ~30kb.

Use an analytics program to check the audience for your site. If a significant chunk of your users use IE9, you need jquery and zepto won't fly. If over a few percent use IE8 and lower and you can't face leaving them stranded without your site, you will need to use jquery 1. If you're targetting that last one, I'm sorry - a lot of new shiny toys won't work for you.

If you're building an html5 app for android/ios/phonegap etc then you're primarily targeting webkit, so zepto does give you big size saving. The primary insight and reason for zepto to exist is that when running on webkit only platforms a lot of jquery's cross platform workarounds are simply unnecessary.

Zepto does also add a couple of touch event handlers to assist with mobile dev, but it's mainly the page weight vs platform support you need to think about.