Google is announcing a new messaging app today. It's called Allo and its main feature is a Google assistant that's built right in. Google says it'll be available later this summer — for free — on both iOS and Android.

Allo (pronounced like "Aloe" and not like "'allo, guv'nor!") is a mobile-only app that you might think is meant to replace Google's other messaging app, Hangouts. But you'd be wrong. Allo is explicitly meant to be a fresh start for Google's new communication's division (which also runs Hangouts and Project Fi).

"It's really liberating to start from scratch sometimes," says Erik Kay, director of engineering, communications products. And Allo does feel like a fresh new start. Its interface is clean and easy to understand, with some clever little innovations on what you've seen in other chat apps like WhatsApp or Messenger.

Let's start with the basics. You sign up with your phone number and you can connect your Google account to it, though there's no need to. You can see the usual chat app stuff: there are sent and received indicators, emoji, and a big set of custom stickers. Amit Fulay, group product manager on Google's communications products team, says that Google commissioned stickers from artists with an eye toward ensuring there was a wide diversity of options — stuff that would work in India, as well as in America.

When you send a photo, it shows up full-bleed in the screen and you can even doodle on it if you want. Another neat trick: before you hit send, you can drag your finger up or down on the button to enlarge or shrink the text. Google calls it "WhisperShout."

If that were all there were to Allo, it wouldn't really have a reason to exist. It certainly wouldn't give you a good reason to switch away from whatever chat app (or, more likely, chat apps) you're currently using. But Google thinks the secret weapon it has in the battle for your thumbs is... Google.

More specifically, it's the Google assistant, the new conversational interface you can use to get information from Google. You can set up a conversation with @google and ask it all sorts of questions. It'll respond with the stuff you've come to expect from typing into a Google search box — but it'll also engage in a bit of a conversation with you. It'll suggest further searches, and give you ways to do things that Google can do — like book a table with OpenTable.

And Google's chatbot is smarter than other chatbots. It has the power of Google's Knowledge Graph, which understands many thousands of "entities" and how they relate to each other. So you can ask more complicated questions that couldn't be resolved just by crawling the web. And if you get bored, you can ask @google to start a game like "guess the movie based on a string of emoji."

But where @google gets more interesting is inside your conversation with your friends. When they send you a message, Allo puts some suggested replies at the bottom. They're called "suggestion chips" and they're powered by a massive and massively smart machine learning engine.

In the example Google showed us, a graduation photo came through. The suggested replies were along the lines of "Congratulations!" and "You look great!" Think for a moment about what it takes to do that. Google recognized it was a graduation photo and then went a step beyond just guessing what it was, it guessed at appropriate responses. And even beyond that, the responses are grouped into little meaning clusters — so you get a range of possible reactions instead of just variations on the same theme.

Google builds up these suggestion chips based on the machine learning it can apply to the way that you actually type. Kay told us that his suggestions were the text-version of smileys because he prefers to use those over actual emoji.

When you "invoke" @google in a chat either by hitting one of those suggestion chips or just typing @google, both you and everybody you're chatting with can see and respond to the answers. So picking a restaurant becomes a group activity where everybody is looking at what you're looking for and helping pick the right one. And debates about who starred in that movie you saw can be resolved immediately and definitively.

At this point, you're probably a little creeped out, so let me tell you what the privacy rules are with Allo. First, all conversations are encrypted "on the wire," which means that nobody on the internet can read them as you send your message. They are read by Google's servers, but Kay assures me that the data is stored "transiently," which is to say that Google doesn't keep your chat logs around to be subpoenaed. And Fulay adds that Google doesn't assign identity to the chat logs on those servers even then.

If that's not strong enough for you, there's also an Incognito Mode — similar to Incognito Mode on Chrome. When you enable it, your conversation is encrypted end-to-end and Google can't read it at all. And notifications from Incognito chats don't reveal their contents on your lock screen, either. It means you won't get the power of the Google assistant, but it also ensures a higher level of privacy. Both Kay and Fulay tell me that Google plans on adding other features to Incognito in the future, such as expiring messages.

Allo is fast and Google is powerful, but is that enough?

At several points during the demo, I couldn't help but think that nothing that I was seeing the Google assistant do was strictly new. But Google, it turns out, is really good at this sort of thing and has been for a long time — so even though the only new functionality here is the conversational interface itself, it still felt pretty powerful.

But there are limits to Allo, and the biggest one is that the only chatbot you'll be talking to is Google. The company isn't diving into the deep end with chatbots in the way that virtually every other tech giant on the planet (save Apple) seems to be doing. Kay says that Google wants "to be thoughtful about bringing multiple things in until we get the interaction right."

That's probably a fine decision for now, especially given the lackluster experience many have had with bots on Facebook Messenger so far. But this is a space that's heating up quickly, so Google may find that it needs to move quickly to keep up.

Speaking of keeping up: Google flat-out hasn't in the messaging space. Hangouts was supposed to be a grand reset and Google's big entry into the field — the company told us as much three years ago. Instead, Hangouts has become something of a rueful, inside joke among Android users. The iOS version is more advanced, but it too could stand to be cleaned up a bit. On the desktop, it still feels like it was designed for a previous age.

And so the big question that any messaging app — especially one from Google — has to face is really simple: how are you going to get people to use your app? Whatsapp and Messenger are nearing or passing a billion monthly active users, and there's an army of chat apps vying for users installs too: WeChat, QQ, Line. And of course, there's iMessage.

It's very hard to compete with chat apps that have a billion users

Kay says that the diversity of Android hardware precludes Google from creating an iMessage-like system that co-opts SMS — not to mention that Allo also needs to work on iOS. Instead, the plan for acquiring users for Allo seems a little, well, unformed. Rather than talk about jump-starting user growth, Fulay emphasized that Google is just focused on making a good app: "The first order of business is just nail the product... make sure we have a product people love." Kay says that "if you don't have a great product that users love and are willing to recommend to their friends, then there's no sense in worrying about distribution."

I'll admit that I think Allo looks like a great product (though I wish that it wasn't strictly phone number-based and mobile-only and therefore tied to to a single phone). But as we've watched other messaging platforms achieve billion-user scale, I also think that convincing them to switch is going to be very hard. Talking to Google in a chat app looks pretty great, but who you really want to talk to are your friends. Right now, they're using something else.

Google can't undo the mistakes it made with Hangouts over the past three years, it can only move forward with a new (and better) app. Allo is definitely both of those things, but it will need to be even more than that to really challenge Facebook and Apple.

Developing...

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