Yes, both Snappy and Slack offer a Free Trial.
Snappy is designed for Large Enterprises, Medium Business and Small Business.
Slack is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Pricing for Snappy Starts at $15/User/Month whereas for Slack Starts at $2.67/Month.
Some top alternatives to Snappy includes Zendesk Support, Zoho Desk, Tidio Helpdesk, Freshservice, Freshdesk, Deskero, Teamwork Desk, HelpDesk, SysAid, Jitbit Helpdesk, lemtalk, Spiceworks Help Desk, LabiDesk, HESK, Support.cc by 500apps and BoldDesk.
Some top alternatives to Slack includes Microsoft Teams, Glip, Google Chat, ChatWork, Dialog, Office Chat, imBee, Takle, SPACE Channel and Teamwork Chat.