Yes, both GitHub and Splunk On-Call offer a Free Trial.
GitHub is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Splunk On-Call is designed for Large Enterprises, Medium Business and Small Business.
Pricing for GitHub Starts at $4/User/Month whereas for Splunk On-Call Starts at $5/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 Splunk On-Call includes Freshservice, PagerDuty, Opsgenie, VictorOps, AlertOps, Spike.sh, opsmanager, Zenduty, StatusCast Incident Management and PagerTree.