iOS Pick: Astro
Leo Laporte's app cap on iOS Today 351 is Astro. This is an email app that uses artificial intelligence. It starts off right away with a chat interface to help you set up your email accounts. Once you get through that, it takes you to a regular inbox view, but there's a button to access the Astro Bot at any time. The bot can help you unsubscribe from mailing lists, archive messages you haven't read in awhile, and you can ask it to send you reminders.
Astro has a lot of modern email features as well, such as a unified Priority Inbox, swipe to snooze messages until a later date, customize notifications, and more. It also can be integrated into other things like Slack and Amazon Echo.
Astro is available for iOS, Android, and Mac.