Yes, both Pivotal Tracker and GitHub offer a Free Trial.
Pivotal Tracker is designed for Large Enterprises, Medium Business and Small Business.
GitHub is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Pricing for Pivotal Tracker Starts at $6.50/User/Month whereas for GitHub Starts at $4/User/Month.
Some top alternatives to Pivotal Tracker includes Smartsheet, Miro, Process Street, Wrike, Notion, Jira, TeamGantt, Teamwork, ProjectManager.com, Microsoft Project, Backlog, Trackboard, Quick Base, ClickUp, Projectsly by 500apps, Height and Project Insight.
Some top alternatives to GitHub includes LiveCode, Codeanywhere, Visual Studio IDE, CodeinCloud, GitLive, Microsoft Azure, GitLab, CodeSee and Bitbucket.