Pumble is a completely free team chat app that allows you to:

- Send messages to other team members
- Post messages on public and private channels to discuss stuff
- Have unlimited access to all your chat history
- Invite unlimited number of users
- Upload and share files with other team members
- Available across devices (Android, iPhone, Web)

Perfect 100% FREE alternative to Slack and Microsoft Teams.

You can learn more about Pumble here: https://pumble.com/