Yes, both Slack and Interact Software offer a Free Trial.
Slack is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Interact Software is designed for Large Enterprises, Medium Business and Small Business.
The starting price of Slack begins at $2.67/Month, while pricing details for Interact Software are unavailable.
Some top alternatives to Slack includes Microsoft Teams, Glip, Google Chat, ChatWork, Dialog, Office Chat, imBee, Takle, SPACE Channel and Teamwork Chat.
Some top alternatives to Interact Software includes Interact, Yammer, Invotra, MyHub Intranet Software, Creative Social Intranet, Attollo Intranet, HCL Connections, Oak Engage and Engynn Intranet.