The way people use email has changed a huge amount since we launched Gmail. With Inbox, we took a step back and did a lot of research into how most people are using email today. What we found was that email works as a todo list for many people, that phone usage is starting to eclipse desktop usage, and that many people have negative feelings towards email because it feels like so much work. We built Inbox as a separate product because we didn’t feel like we could solve those problems by just adding more features on to Gmail. We needed to start from scratch to build a tool that really helps you stay on top of your life.
In many ways, Inbox is a simplified mail service optimized for mobile. It surfaces important information, helps you get things done and organizes your messages. It also goes beyond email. "Inbox allows you to create your own reminders, which really allows it to function as a true to-do list that reflects your own priorities, and offers assists to help you get things done. Inbox goes a lot farther into personal assistant territory and helps you stay on top of the things that matter. We see Inbox as a tool for managing your life, not just your mail," says Jason Cornwell.
Will Inbox replace Gmail? Here's Jason's answer:
In the short term, no. In the very long term, we hope so. Inbox is something new - that's why we’re launching it as a separate product. We care deeply about Gmail and Gmail users, but in the long run as we add more features to Inbox and respond to user feedback we hope that everyone will want to use Inbox instead of Gmail. Ultimately, our users will decide.