Inbox by Gmail is a new Android app by the same people who brought you Gmail, but it’s not Gmail, it’s a completely different type of inbox which sorts your mail for you the same way a personal assistant would. Inbox app automatically categorizes your incoming messages into “Bundles,” which are broken out into things like Travel, Purchases, and Social. You can also create your own Bundles from tags, or by grouping messages into Bundles.
It also has a very useful ability to snooze actions and emails. For example, if an email comes in that you can’t act on until you get to your desk at work, you can snooze it until the next morning you arrive there.
The service requires an invite. Send an email to inbox@google.com to request your invitation.