I didn't use Mailbox, but I think one of the key features is the snooze button, that makes an email disappear from your inbox and then reappear later. I think a

I didn't use Mailbox, but I think one of the key features is the snooze button, that makes an email disappear from your inbox and then reappear later. I think at the time Mailbox came out Google didn't offer that feature. The GMail webapp still doesn't have it but now Google Inbox does.