Tasks
HeyOtto extracts action items from your mail and bundles them into one task list.
From email to task
If an email requires action, you can turn it into a task — with title, context and the linked email. Open Tasks in the sidebar for the full overview, with due date and urgency.
Microsoft To Do
From the reading pane, you add an email directly as a task in Microsoft To Do with the button + Task in Microsoft To Do.