Yes, both Flow and Microsoft Power Apps offer a Free Trial.
Flow is designed for Large Enterprises, Medium Business and Small Business.
Microsoft Power Apps is designed for Large Enterprises, Medium Business and Small Business.
The starting price of Flow begins at $6/User/Month when Billed Yearly, while pricing details for Microsoft Power Apps are unavailable.
Some top alternatives to Flow includes Quickbase , Smartsheet, ClickUp, Zoho Projects, Wrike, TeamGantt, Teamwork, ProjectManager.com, Microsoft Project, ProWorkflow, Trackboard, TaskBranch, Quick Base, Height, Task Flow and Project Insight.
Some top alternatives to Microsoft Power Apps includes Mendix, Oracle Application Express, AgilePoint NX, LiveCode, Appup by 500apps, Simplifier, DOCOVA, Netcall Liberty Create, SDMT LCAP/LCNC Platform and The m-Power Development Platform.