The Postmark app has redesigned its Activity page to improve user experience, making it easier and faster for users to find emails. The new layout features a table structure with each message event on the left, allowing for easy scanning of the page. Additional features include an "Delivered" event, updated labeling of "Sent" status as "Processed", information-rich tool tips, and the ability to export search results to CSV directly from the UI, up to 500 records. The redesign aims to provide clarity and speed in finding emails, addressing previous issues with data comprehension and filtering capabilities.