Inbox by Google
Inbox by Gmail is an app from the Gmail team that helps to:
See highlights of flights, locations, calendars without digging through emails
Put reminders at the top of you inbox
Manage, snooze emails and reminders to come back to your inbox when you want
Use bundles to group email messages and get clutter out of your way
Manage unbundled messages when they appear individually in the inbox
Inbox bundles emails to be more organized.