Yes, both Slack and Quickflow offer a Free Trial.
Slack is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Quickflow is designed for Medium Business and Small Business.
Pricing for Slack Starts at $2.67/Month whereas for Quickflow Starts at $7/Month.
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 Quickflow includes Microsoft Flow, Zoho Flow, Breakout, ZapUp by 500apps, Browserflow, automation.re, Qualified, Built.io Flow, Workvivo, Flowall, Cflow and Consider.