Starting with Chrome 50, calling play() on an <audio> or <video> element will return a Promise, which you can use to determine whether the playback actually started.

This smooths over the longstanding cross-platform differences in automatic playback policy between mobile and desktop browsers.

Hey, my Chrome Dev Summit talk is up already!

It covers the performance benefits of the App Shell + service worker model, and two libraries that can simplify your service worker implementation, sw-precache and sw-toolbox. 

The Google I/O web app (https://events.google.com/io2015/) used #ServiceWorker s extensively. They powered led to a faster web app that supported push notifications and worked equally well with or without an Internet connection.

I wrote up our experiences, best practices, and gotchas—with a special focus on the sw-precache and sw-toolbox libraries that you can use in your own web apps—at https://developers.google.com/web/showcase/case-study/service-workers-iowa

I use WebStorm with a personal license at home, IntelliJ at work. There's nothing I use in IntelliJ that's missing from WebStorm.

As many plug-ins as Sublime Text or Atom, but with a built in terminal and amazing Git integration.

Give WebStorm a try!

(Yes, I understand the folly of a my-editor-is-best post...) 

I've just released a new version of sw-precache, which automatically generates a #ServiceWorker script for you based on the contents of a local directory. There's more background at http://updates.html5rocks.com/2015/02/offline-first-with-sw-precache

New to this release is a command-line interface. I'd recommend including sw-precache as part of a build process, to regenerate the service worker each time local files change, but the option is now there if it's easier for your to run it as a CLI. I could image this coming in handy for folks whose build process uses the "scripts" configuration in package.json and is kicked off using npm.