Yes, both Trello and Fronter.io offer a Free Trial.
Trello is designed for Individuals, Freelancers, Large Enterprises, Medium Business and Small Business.
Fronter.io is designed for Large Enterprises, Medium Business and Small Business.
Pricing for Trello Starts at $5/User/Month when Billed Yearly whereas for Fronter.io Starts at $19/Month.
Some top alternatives to Trello includes Quickbase , Smartsheet, ClickUp, Zoho Projects, Freshbooks, Jira, Basecamp, Wrike, monday.com, Asana, Teamwork, ProjectManager.com, Microsoft Project, Worksuite, Trackboard, Quick Base, Todoist, Resource Guru and Height.
Some top alternatives to Fronter.io includes Front, QuickReviewer, Hightail, Coment, MockVisual, Featurebase.app, fdbck.io, Superflow and Feedback Monkey.