Human boy working on web standards at Google
Background Fetch lets you handle large downloads, even if the browser closes.
Aborting fetches using a new web primitive – The abort controller
The visual viewport API gives you details on how the user zooms and scrolls around your page.
Navigation preload lets you overcome service worker startup time by making requests in parallel.
Async functions allow you to write promise-based code as if it were synchronous
A deep-dive into the service worker lifecycle.
Background sync is a new web API that lets you defer actions until the user has stable connectivity. This is useful for ensuring that whatever the user wants to send, is actually sent.
Chrome 46 brought new methods to caches, as does Chrome 47, and probably 48. It never stops.
Every click interaction in mobile browsers is hampered with a 300ms delay, but that's gone in Chrome 32 for mobile-optimized sites!