Here is a feature list according to a Google memo (colorful commentary is theirs, not ours):
Brand new UI. We’ve designed a new UI that’s applied across all clients and promotes conversations.
Stay in sync. With just one conversation list and experience across mobile and desktop, everything is always in sync. Install the Chrome app, the Android app, and iOS app.
Desktop app. Stop laying whack a mole across blinking browser tabs. With the new Chrome app your conversations continue outside of the browser.
Keep a group conversation going to coordinate with your team, and start a Hangout with a single tap whenever you need to talk face-to-face.
Be notified…just once. Get notifications on your two phones, tablet, laptop, and desktop. Open it on one and watch the others disappear. If you’re actively using your computer or phone we’ll even intelligently notify you on just one of those endpoints. Magic!
Message more than just text. Add a photo to the conversation and/or send some of the 800+ emoji to your coworkers. Kittens and poop are particularly helpful in explaining complex issues.
Get nostalgic. Scroll back in time and relive any (on-the-record) conversation, on any device.
More ways to talk. For the first time we are building a first class iOS experience. Try out our very early preview on your iPhone or iPod Touch.
