Google’s lack of a unified messaging platform became something of a mystery, since it seemed like Google had all the necessary pieces. "There is a lot of code that existed that from a high-level point of view, if we just crunched it together, [it theoretically] should’ve turned into one product," says Singhal. The messaging experience was neither consistent or unified, and it wasn’t even easy to use. Google+ Messenger, a real-time communication platform that launched last year, was the first piece, but it only existed inside of Google+. Talk was another, but it was based on an old standard that predated the advent of cloud computing. Hangouts was third, a real-time video chat product embedded in Google+. Gmail had its own real-time communication team. Google Voice was the final piece, an infrequently updated relic that seemed destined for Google’s infamous spring cleaning chopping block.

Talk, for example, was built to help enterprise users communicate better, Singhal says. "The notion of creating something that’s social and that’s always available wasn’t the same charter as we set out with when we created Talk." With Hangouts, Singhal says Google had to make the difficult decision to drop the very "open" XMPP standard that it helped pioneer.

Google instead spent its time building out mobile apps like Gmail, Google Now, Google Drive, and Google+, allowing its early lead to evaporate. As Singhal puts it, "When we started looking at the project we realized, and this sounds obvious in retrospect, that we built a lot of the communication products at Google without smartphones, without social networks in people’s lives."

Once upon a time, Google was at the forefront of the messaging game. In 2005, the company launched Talk, essentially the best experience in what was then the hottest category: instant messaging. Since then, a new category of mobile messaging has emerged: always-on chat with rich media attachments like voice memos, read receipts, and group chats. BlackBerry Messenger drove millions to buy a BlackBerry, and in recent years tiny startups like WhatsApp and established players like Facebook have grown to process billions of messages a day. In April of this year, people sent more messages using chat apps than SMS while Google sat on the sidelines with its little-used Google+ Messenger app.

The watershed moment came with Google+, which proved that Google could — and should — organize a company-wide effort to implement a single idea. Years of work had shown that this core product couldn’t be created by just one team, or a handful of engineers working on their 20-percent time. "We started pulling the team together about two years ago," says Singhal. "It’s like The Avengers — we’ve had to pull together different styles and different cultures [from across Google]." The Hangouts team as it exists today is a combination of thiese pieces, a new backbone to hold together the real-time infrastructure that will power the next age of Google. Like with Google+, Singhal explains, the difficulty in messaging was "to integrate, aggregate, and crunch these different systems together."

Although Google Talk seemed like a good foundation for a messaging app, Google decided it needed to start from scratch. "We had to essentially rebuild everything," says Singhal. To create Hangouts from the guts of a decade’s worth of insular communication products, Google had to pull in engineers from across the company — many of whom were working separately on this very problem. From the outside, the company looked like a crystal palace of servers and engineers, but on the inside those same engineers weren’t working in concert, especially on messaging. "What’s funny is that most of them actually were trying to build this unified product independently," says Singhal, but separately, no one could get it done.

Cloud messaging

On the surface, Hangouts is essentially a messaging app in the same vein as WhatsApp and Facebook Messenger. Hangouts replaces Google Talk, Google+ Messenger, and the classic Google+ Hangouts video chat.

The app — available on Android, iOS, and Chrome (but not Windows Phone or BlackBerry) — starts with text conversations. You're presented with a list of your recent conversations instead of a contact list. That's the first sign that this is more of a mobile messenger than a traditional instant messaging client, a distinction that becomes even clearer once you dive into a group chat or one-on-one conversation. Conversations get names, like chat rooms, and it's simple to add an image or one of Google’s 850 new hand-drawn emoji.

Major Google messaging moments Google Talk launches

Google Talk integrated into Gmail, adds XMPP support

Android launches with Google Talk app included

Google Chat launches in Gmail , includes voice and video chat

Google Voice launches

Google Wave announced

Google adds chat to Google Docs

Google adds live video chat to Android

Google Voice integrated into Gmail

Google+ launches with video Hangouts and Huddle, an Android messenger

Google launches mobile Hangouts for Android

Google launches Hangouts in Gmail

Google says it's put a lot of thought into reconsidering presence, and it actually works better in Hangouts than on other apps. Instead of using "read receipts" (first popularized on BBM and coming this summer to iOS and Android) or a blanket online / offline indicator, Hangouts inserts tiny little square avatars into the chat history, called "watermarks." These watermarks show when somebody else is typing, but they also indicate how far others have read in the conversation.

The watermarks create a new sense of immediacy missing in ordinary text conversations

The watermarks create a new sense of immediacy missing from ordinary text conversations — you can see who is around and who isn't at a glance. Product manager Ben Eidelson says watermarks — like video Hangouts — reproduce the signals and cues we receive in face-to-face conversation. "It’s kind of like making eye contact," says Randall Sarafa, another product manager on Hangouts. The flip side of this new system is that you lose the more traditional "Active / Away" presence indicators that Google Talk users have grown accustomed to. It’s a hybrid of instant messaging and mobile messaging, though Hangouts will on some levels remain interoperable from Google Talk.

Hangouts keep your messages in the cloud — which isn’t exactly revolutionary, but since it's Google's cloud, there are some unique benefits. Every Hangouts conversation is stored online (and is accessible from any Hangouts app), but there is an option to toggle off history if you'd like to go off the record. The service’s Google+ integration is one of the best features in the entire product: every photo that you or a friend posts is automatically saved in a private, shared album on Google+. For example, after a year of using Hangouts, it will be easy not just to trace the text conversations your budding relationship has produced, but to track the photos you’ve shared over time. The feature is so obvious and so compelling that it could theoretically do what few Google initiatives have managed thus far — give a huge number of users a real sense of affinity with Google+.

Hangouts also benefits from Google+’s video conference tool — the "old" Hangouts. You can immediately start a video chat with up to 10 people with one tap, but voice-only conversation is a hassle since you’ll have to "mute" your video feed. Aside from audio calls, Hangouts has some other glaringly obvious missing features, like SMS. Google hasn't integrated SMS with Hangouts, either because Google doesn't want to annoy carriers or simply because it hasn't gotten around to it yet. Yet, both Apple and Facebook have proven with iOS’ Messages and Android’s Facebook Messenger that it can be tastefully done. Also, most of Google’s competitors let you broadcast messages, or embed video, voice messages, location, or any of the "stickers" that have become strangely popular. Finally, Google Voice, a product that could have been revolutionary but has instead languished, has been pulled into the Hangouts team with the promise of future integration. Singhal says that "this is the future for Google Voice," but offers no timeline for the integration of the the two products.

Aside from the missing features we’ve come to expect from new messaging platforms, Hangouts is also lacking your friends, who are using a great variety of messaging apps from WhatsApp to Kik. Hangouts hasn’t had years to cultivate hundreds of million of users worldwide like industry leader WhatsApp, which makes it a tough sell considering it’s short on features. However, most of the top apps on the scene don’t have desktop companions — a space ripe for the taking. If the masses decide that they do value a desktop app to complement their mobile one, Hangouts will be among the first to provide one, alongside Facebook Messenger and Viber. Plus, Google's size and ubiquity has proven to be an advantage when it wants to move into new areas.

Ultimately, Google has built a solid messaging app with a strong foundation that’s sure to win many converts, but it’s hard to ignore how late the company is to the game. With Facebook, Apple, BlackBerry, WhatsApp, and now many others well established in the messaging game, it’s a very crowded space. If Hangouts wants to make a stand, it will do so on the backs of Google’s 425 million Gmail users.

One Google

Google in 2013 is a very different company than the one most of us still envision. Larry Page’s ascension to CEO was the first step towards crafting a company more focused on big, integrated products. Gmail, Docs, and Maps now have a consistent look on both web and mobile, and although Google still has its share of experimental products like Glass and driverless cars, the days of the world-changing 20-percent projects are waning. The next Gmail just isn’t coming from two or three engineers on lunch break.

Hangouts takes massively powerful cloud services and marries it to a consumer product

Hangouts, like Google+, grew out of this internal shift, a revelation that was cultural as much as it was technical. Touchstone examples of the "One Google" product philosophy, they both serve as a "spine" for the company’s various products. "Google+ really was the template and the critical lesson that helped us believe that this type of project was possible," Singhal says. Hangouts may have taken years to build, but it’s devoid of the siloed approach Google has taken thus far with new products like Wave and Buzz. Hangouts takes what's best about Google — massively powerful cloud services — and marries it to a consumer product.

With Hangouts, Google has created a unifying backend for the future of its real-time products; Singhal describes it as "the single communication app that we want our users to rely on." It's a platform in an almost literal sense — something to build on that's not yet finished. In a way, Hangouts is an extension of Gmail’s product philosophy: to create a conversation between people instead of a chaotic flurry of messages. Google radically changed email in 2004 with its inclusion of "threaded conversations" in Gmail, but it never translated its success when the world went mobile. Google may have missed the boat on the mobile messaging revolution, but with its new real-time infrastructure in tow, it should be ready for the next revolution, whether it be holographic Hangouts or virtual email. "We don’t see Hangouts as a messaging product, we see it as a communication product," says product manager Kate Cushing. The only question is, when the next communication app trend hits, will Google be first or last?

Video by Jordan Oplinger & Stephen Greenwood

Edited by: Jordan Oplinger

Additional Editing: Billy Disney

Audio Mixing: John Lagomarsino