Yes, both GitHub and Rely.io offer a Free Trial.
GitHub is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Rely.io is designed for Large Enterprises, Small Business, Medium Business and Individuals.
Pricing for GitHub Starts at $4/User/Month whereas for Rely.io Starts at $20.00per user / month when Billed Yearly.
Some top alternatives to GitHub includes LiveCode, Codeanywhere, Visual Studio IDE, CodeinCloud, GitLive, Microsoft Azure, GitLab, CodeSee and Bitbucket.
Some top alternatives to Rely.io includes and undefined.