Fluid UI

Overview

Fluid UI is a browser-based tool for shaping mobile-app mockups into interactive prototypes that can be shared and reviewed. It suits designers and product teams who need feedback on flows before building them; its strongest case is the combination of prototyping and review, though paid-plan user limits can make team pricing a constraint.

Projects can be created, edited, previewed, shared and exported. Taps, swipes and clicks make a prototype navigable, while component libraries and page effects help communicate an idea’s appearance and behavior.

Key features

• Component libraries: More than 2,000 built-in components cover Material Design, iOS, Windows and wireframe libraries. That range offers useful starting points for several interface styles rather than locking work to one system.
• Interactions and animation: Prototypes can respond to taps, swipes, clicks and other gestures. Pop-in, fade-in, flip and show effects help explain transitions, but are presentation tools for a prototype, not a finished product interface.
• Collaboration and review: Cloud-saved work supports real-time collaborative prototyping. Reviewer mode adds shared click-throughs, chat, annotations and comments, and remote user-testing sessions are supported. These tools suit teams that need input on a flow, although the Solo and Pro plans each include only one user license.
• Support and project continuity: Built-in live chat support is available 16 hours a day. Projects are continuously saved, with daily, weekly and monthly backups and restoration from any save in the editor; this gives users several ways to recover work.

Pricing

Fluid UI is freemium, with a free lifetime account and paid plans billed monthly at the stated rates. A free trial is also offered. The free plan’s project and user limits are not established by the plan terms here, so it is difficult to judge how long it will suit active work.

• Free: Free forever. Best for trying the service or maintaining a small project if its caps fit; the plan’s project and seat allowances are not established.
• Solo: $8.25/month for 5 active projects, 1 user license and unlimited reviewers. This is the least expensive paid option for an individual who wants reviewer access, but it does not provide export, print or comment according to the plan terms.
• Pro: $19.08/month for 10 projects, 1 user license, unlimited reviewers, export, print and comment. It fits a solo practitioner who needs those output and feedback options, but not a multi-seat working team.
• Team: $41.58/month for unlimited projects, 5 users, unlimited reviewers, export, print, comment and real-time team collaboration. It is the clearest fit for a small group working together; larger teams should account for the five-user allowance.

Unlimited reviewers distinguish review access from paid user licenses: the Solo and Pro plans remain single-license plans even when many people can review. Check the seat allowance against who needs to edit or collaborate before choosing.

Platforms

Fluid UI is web-based and runs in Firefox and Chrome. It offers an installable desktop client and Android and iOS preview apps, with platforms spanning Android, iOS, Linux, macOS, web and Windows. That breadth supports creating in a browser or desktop client and previewing on mobile devices.

Fluid UI says pages use industry-standard 256-bit encryption for data sent to the service. Its privacy notice places servers in a Rackspace US data center, describes Rackspace as GDPR compliant, and allows account-data deletion requests by email. Realex Payments processes and stores card details; Fluid UI says it does not keep card details on its own servers.

Who it's for

Designers, entrepreneurs, developers, product managers and professors are among the audiences Fluid UI identifies. It is a sensible choice for people communicating an idea through a clickable mobile or web prototype, especially when collaborators need to comment or take part in remote user testing. A solo user who needs export and review features can move to Pro; a five-person group gets a defined collaboration tier. It is less suited to teams that need more than five paid users on the listed Team plan.

Pros and cons

• Pro: The built-in libraries cover four named design and wireframe systems, reducing the need to start every mockup from blank screens.
• Pro: Shared click-throughs, comments and remote testing connect prototype presentation with feedback rather than stopping at screen creation.
• Pro: The Team plan combines five licenses with unlimited projects and real-time collaboration.
• Con: Solo and Pro each license one user, so a second paid collaborator requires the more expensive Team tier.
• Con: Solo omits export, print and comment, while the free plan’s project and seat caps are not established; users should confirm that a cheaper tier covers their workflow before committing.

Alternatives

Readers comparing design and prototyping products can also browse UI design tools, Wireframing Software, Prototyping Software and Game UI Design Software.

• Mockplus has a free Basic plan for 10 users and 10 active projects, so consider it if those free-plan allowances matter more than Fluid UI’s listed collaboration and review tiers.
• UXPin offers a limited free plan after its 14-day trial, with 2 prototypes and 50 AI credits; it is an alternative for readers weighing that post-trial allowance.
• Figma Slides has a free Starter plan with unlimited drafts and AI-credit allowances; choose it if those stated limits suit the work at hand.
• Justinmind offers a free plan with 1 project, unlimited screens and viewers, and UI design and wireframing; it may suit a single-project workflow.
• Proto.io has a free plan limited to 1 user, 1 active project, 5 prototype screens, 10 MB storage and no additional reviewers; consider it if that small-scale allowance is sufficient.
• ProtoPie has a free plan limited to 2 cloud prototypes, 8 scenes per prototype and 50 MB of cloud storage; it is an alternative when those prototype limits fit.
• Marvel offers a free plan for 1 user and 1 project, while its Pro plan is $12.00/month billed yearly; compare it if those plan terms better match your project needs.
• Lunacy offers a free plan with up to 10 cloud documents, 10 document editors/exporters and 30 days of version history; consider it when those document allowances are a closer fit.

Verdict

Fluid UI is a strong fit for solo designers and small product teams that need to turn screens into interactive demos, share them for review and collaborate in real time. Its component libraries and review workflow are the main reasons to choose it. Look elsewhere if your team needs more than five paid users, or if a single-license plan must include export, print and comments without stepping up to Pro.