Adobe
Yes, both Backlog and Marker.io offer a Free Trial.
Backlog is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Marker.io is designed for Large Enterprises, Medium Business and Small Business.
The starting price of Backlog begins at $29.16/Month when Billed Yearly, while pricing details for Marker.io are unavailable.
Some top alternatives to Backlog includes Quickbase , Smartsheet, ClickUp, Jira, Wrike, TeamGantt, FogBugz, Teamwork, ProjectManager.com, Trackboard, TaskBranch, Quick Base, TestRail, Height and Project Insight.
Some top alternatives to Marker.io includes The Bug Squasher, BugHerd, Buglog, TrackJS, Ybug, BugHost, DebugMe, Bug-Track.com, Disbug and Toybox.