Google's on a mission to reinvent email. Its weapon: Inbox, a standalone app that launched last week.

Inbox aims to make email more useful with several new tools. It surfaces relevant content (photos, for example) and information from within individual messages so you don't have to open anything to get at what you really want. Bundles sort your messages for you, letting you find important messages faster. Plus you can add your own reminders that work with Google Now.

But there's something important that Inbox isn't: Gmail. Although the whole aim of Google Inbox is to make email more useful, it's not intended to replace the Gmail experience. Yet.

"The way that people deal with their inbox has changed dramatically," says Alex Gawley, product director of Gmail and Inbox. "We found people really wanted to run their life through their inbox — there was so much information there — but it was a lot of work for them."

Inbox vs. Gmail

Inbox is so radically different from Gmail (and other email services) that Google is clearly proceeding cautiously. If Facebook is any indication, users tend to react negatively to big redesigns when they have no say in them, and Gmail's introduction of automatically organized tabs last year received its share of criticism before everyone quieted down and saw how useful it was.

Compared to Inbox, Gmail tabs were merely a new coat of paint. The app is a full-on email renovation, complete with heavy doses of Material, Google's new design philosophy embodied in Android 5.0 "Lollipop." By launching Inbox as a standalone app, Google can test the waters on Inbox. After all, no one wants another Google Wave, the company's ill-fated attempt to combine instant messaging, collaboration and project management into a single interface.

Still, although Inbox's creators clearly see the app as the future of email — and Gmail. The whole thrust of Inbox is that it solves some real problems with email as it exists today, and it does it through three different tools.

Inbox features and problems

First is Highlights, which surfaces content without the need to open messages. If you have a family member who constantly shares photos and videos with you via email, you'll appreciate Highlights putting all their attachments together in a strip that you can scroll through like a slideshow.

Highlights also surfaces other attachments, such as PDFs and Word documents, and even specific information like links and flight itineraries. Even better, they can be dynamic, constantly

"If your flight information changes, your email stays the same, but the Highlight goes farther," explains Jason Cornwell, lead designer for Gmail and Inbox. "It goes out to the web and pulls in up-to-date tracking information. You can see the terminal and the gate right in the Highlight."

Bundles are basically an extension of Gmail's existing tabs. Inbox will automatically group together similar messages — such as promotional emails from deals sites — letting you quickly swipe through them and get rid of the rest. Several Bundles are preloaded (Travel and Purchases), but you can create your own, too.

"Lots of people get 50 to 100 promotions a day," says Cornwell, "and we keep on getting them because occasionally there's that diamond in the rough — that deal you really want to take advantage [of]. So most people don't unsubscribe to them. What Bundles allow you to do is look across a whole category of messages all at once."

Inbox's Bundles are an extension of Gmail's tabs, grouping emails of a certain type together. Image: Mashable, Elizabeth Pierson

Finally there's reminders, which Cornwell says is the last ingredient needed to turn Inbox into a to-do list replacement. Reminders automatically get pinned to the top of your Inbox, but — like any message — you can "snooze" them away to deal with at a later time. They also work across devices.

"If you create a reminder on your Wear watch or in [Google] Now, that's going to cause your phone to buzz, but then it ends up back in Inbox if you snooze it away."

Since its launch, Inbox has garnered its share of criticism. For starters, the design makes liberal use of white space, so the app displays fewer messages onscreen at once. However, Cornwell says that's actually not an issue since, thanks to Bundles, you can actually deal with several messages at once, whereas in other apps you'd archive them one by one.

Inbox definitely overlaps with other Google services — mainly Google Now, the company's catch-all people organizer that's based on Android phones (though there's an iOS app, too). Inbox's creators don't see that as a problem, since both apps work with each other, using the same reminders, for example. Inbox just provides another window to them, which happens to be integrated with email.

You'd think Inbox's first customers would be workaholics who already live in their Gmail inboxes, but Google has so far held back Google Apps support. Cornwell says it is coming "soon."

The (r)evolution of email

Inbox has a noble goal, and its tools are promising. Will it replace Gmail? More to the point: Will Inbox change how we think about email?

Rewinding 10 years, Gmail did just that when it debuted in 2004. Before that, inboxes were a cluttered, spam-filled mess that usually existed on a local server. Although web email had been around for a while, Gmail pushed it forward with better storage, a cleaner interface and the the-new conversation view.

Gmail was so successful that it ended up redefining what we expect from a web email service. Inbox clearly wants to do so again, but it'll only work if it really addresses the email issues of 2014. Today the problem isn't spam per se, but quickly identifying the best, most relevant messages and pushing the rest to the background. And once we've done that, making the actions you need to take on those messages as efficient as possible.

"We think this is the inbox designed for the problems we're going to see in the next 10 years, and that's how we're going to build on this," Gawley says. "We also know there's a whole bunch of things that people are doing inside Gmail that we want them to be continuing to be able to do as well. We hope, in the long run, that most of our users will be on Inbox."

Inbox could be the future of email, but it requires a rethinking of the email app. Whether or not it replaces Gmail will depend on if Google has estimated correctly how much rethinking is too much, and how much is just right. For now, that's up to the users.

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