Slack auto-erases messages after a year. Back them up regularly. Free plans only allow exporting public channel messages. Pro, business, and enterprise plans can export everything. To back up Slack ...

I really like MS Teams. After the disaster that was Lync, and Skype, and then the new version of Skype (none of which were not bad products on their own, but their integration and syncing features ...

PARIS, FRANCE - FEBRUARY 06: In this photo illustration, the Slack logo is displayed on the screen of an Apple iPhone in front of a computer screen displaying a Slack logo on February 06, 2019 in ...

Slack doesn't have a 300 user limit but good luck fitting that many or more users into a free Slack account. 10,000 messages goes FAST with 300 people all talking.