The Free Plan offers 2 active projects with at most 300 stencils each and 5 MB of storage. This plan does not include: Master Pages, Real Time Collaboration, Privacy Settings, Unlimited Revisions, Unlimited Project Archiving and Teams.
Balsamiq has a very easy to use drag and drop interface that lets you quickly build and adjust your mockups. The UI is centered around low-fidelity wireframes that help focus the reviews on the core layout and functionality instead of getting hung-up on visual design.
To ensure that users needs are met, Sketch has been developed by designers for designers. This results in a fully vector-based workflow for scalability of any asset. Sketch is lightweight, fast, and pixel accurate with true-to-css styles. This makes it as fast as any wireframing software for early...
A free tier with all mockup functionality is available. Free tier is limited by lacking ability to save mockups privately and additional services provided by Precursor like voice chat and registered subdomains.