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Inbox by Gmail app for iPhone will use AI-powered Smart Reply feature to respond to messages for you


Google’s Inbox by Gmail app for iPhone is one of the best things to happen to personal email management since email was invented (at least, it is for Gmail users). Using Google Now’s power, it can automatically create calendar events, sort out your junk and priority emails and suggest reminders. Now it’s about to get a whole lot smarter.

Making use of the company’s deep neural network tech (commonly known as AI) Inbox by Gmail will soon start giving suggested responses whenever you receive an email. That means that, instead of typing out entire sentences, it’ll offer three suggestions it thinks you’re most likely to use based on the email you received. The update will hit the app later this week and joins a whole host of other AI-powered moves made by Google recently, including YouTube thumbnails, better voice search and nightmarish picture editing, among others.


In its blog post about the update, Google explains how the technology works, stating that as the email comes in, one network encodes the email by consuming the words one at a time and then produces a vector, or list of numbers. This vector essentially captures the message of what the email means. A second network then uses this ‘thought vector’ and creates a grammatically correct reply one word at a time. To the user, it should feel fast, intuitive and natural. But the process of building this capability wasn’t without its challenges:

One challenge of working with emails is that the inputs and outputs of the model can be hundreds of words long. This is where the particular choice of recurrent neural network type really matters. We used a variant of a “long short-term-memory” network (or LSTM for short), which is particularly good at preserving long-term dependencies, and can home in on the part of the incoming email that is most useful in predicting a response, without being distracted by less relevant sentences before and after.

Of course, there’s another very important factor in working with email, which is privacy. In developing Smart Reply we adhered to the same rigorous user privacy standards we’ve always held — in other words, no humans reading your email. This means researchers have to get machine learning to work on a data set that they themselves cannot read, which is a little like trying to solve a puzzle while blindfolded — but a challenge makes it more interesting!

Since testing, Google’s engineers have been surprised by how good the neural network-powered Smart Reply system is at getting it right. If you have the Inbox app installed on your iPhone, you’ll be able to download the AI-infused update from next week. If you haven’t used it yet, you can grab it from the App Store for free.

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  1. lincolnsills - 7 years ago

    “Of course, there’s another very important factor in working with email, which is privacy. In developing Smart Reply we adhered to the same rigorous user privacy standards we’ve always held —” I literally laughed out loud when I read that lie.

    • mrobertson21 - 7 years ago

      It’s fun to pretend that the data Google sells isn’t anonymous.

      • gatorguy2 - 7 years ago

        It’s fun to pretend Google sells your data.

  2. Iphone users usually don’t like google products by pretending that Google sells their personal info to others, but i’m wondering why there is a lot of them using gmail at least all iphone users i know have gmail as their main email account, and with this upcoming AI thing update, you would be obliged to share some of your personal info with google in order to increase the accuracy, so are they going to leave gmail for another email service or what ? i hope for them yahoo won’t be am option…

    • beardman - 7 years ago

      If Apple would allow to set up my Apple mail as primary email account, I wouldn’t use any other mail account like Gmail.

  3. I dont really care about the privacy stuff, if Google wants to read my emails, fine… But, I’ve stopped using Gmail app and the Inbox app because Google seem to develop their programs to a certain point and just stop. And they have a bad habit of ignoring iPhone features which I like to have…like 3d force touch and apple watch extension.. Gmail app nor inbox has any support for this, and if I know google well it will never get any of this.

  4. spenceryang - 7 years ago

    Not sure about the privacy of this. The UI looks great though. My team prefers to use applications that do not need to read my emails. for desktop and team keyboard for mobile apps work great!