Yes, both Ubertesters and Userback offer a Free Trial.
Ubertesters is designed for Large Enterprises, Medium Business and Small Business.
Userback is designed for Individuals, Freelancers, Medium Business and Small Business.
The starting price of Userback begins at $14/Month when Billed Yearly, while pricing details for Ubertesters are unavailable.
Some top alternatives to Ubertesters includes TestRail, ReQtest, Bug-Track.com, Disbug, CloudQA, Kualitee, QuAck, UnbugQA, Crash Catch and TestUnity.
Some top alternatives to Userback includes Backlogs, Backlog, ReportBugz, Buglog, Usersnap, Ybug, Bug-Track.com, Disbug, Feedback Monkey and Toybox.