Slack offers Free Trial, but Boundless does not.
Slack is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Boundless is designed for Individuals, Large Enterprises, Medium Business and Small Business.
Pricing for Slack Starts at $2.67/Month whereas for Boundless Starts at $19/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 Boundless includes Unbounce, VWO Deploy, Wix, Webflow, Builder, Webstraw, WebsiteBuilder, Bookmark Website Builder, Webs, Format, SiteBuilder.com, HelloWeb, GoDaddy Website Builder, NinjaSites by 500apps and Web.com.