Do you want more than just comfortable communication? Then take a look at the Slack app directory. Here you will find over 2 thousand apps for a wide variety of tasks. Slack supports integration with third-party software, significantly expanding the capabilities of the messenger. You can integrate contacts from Hubspot, Google, etc., install an app for voice communication and send SMS from Slack, such as Clerk, select useful bots, etc.
Despite its capabilities and popularity, Slack has a free version. Anyone can evaluate the benefits of the product and decide on the appropriateness of use. Free Slack is great for small IT teams. If it is not enough for you, then choose one of 3 paid plans with additional bonuses.