Yes, both Slack and AzureDesk offer a Free Trial.
Slack is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
AzureDesk is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Slack Starts at $2.67/Month whereas for AzureDesk Starts at $33/User/Month when Billed Yearly.
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 AzureDesk includes Zoho Desk, Zendesk Support, ManageEngine ServiceDesk Plus, Freshservice, Freshdesk, Teamwork Desk, HelpDesk, SysAid, Jitbit Helpdesk, Desky, ReadyDesk, HelpdeskEddy, LabiDesk, Help Desk Premier, Revelation helpdesk and BoldDesk.
