streaks
tell me what these "streaks" are and what I can do with them. or are they just for kids?
72nd
ranked
It's a fun way to get rewarded for checking, reading or triaging your mail. Just like many apps today have streaks and fun for their regular, keeping-coming-back-users.
Of course you do not have to participate. It's not forced. You can disable this by going to More > Your Streaks. Thanks!