Fluid UI vs Frame0

Fluid UI is a web-based tool for making, previewing, sharing, and exporting mobile app mockups. It supports interactive web and mobile prototypes with taps, swipes, clicks, and other gestures, plus page effects such as fades, flips, and pop-ins. The built-in library contains more than 2,000 components spanning Material Design, iOS, Windows, and wireframe styles. Teams can collaborate on cloud-saved projects in real time. Reviewer mode supports shared click-throughs, chat, annotations, and comments, and the service also supports remote user testing sessions. Fluid UI runs in Firefox and Chrome, offers an installable desktop client, and has Android and iOS preview apps. There is a free plan and a free trial. Paid plans include Solo at $8.25 a month for five active projects, one user license, and unlimited reviewers; Pro is $19.08 a month, and Team is $41.58 a month.

Frame0 is desktop wireframing software for making low-fidelity, sketch-style wireframes and prototypes. Its component library covers desktop, mobile, smartwatch, and web interfaces, with adjustable component states, and it includes more than 1,500 Lucide-based sketch-style icons. Shapes can link to pages, external URLs, or navigation actions; prototypes can be presented and exported as interactive HTML or PDF files. The app also supports flowcharts, entity-relationship diagrams, and UML use case and class diagrams. Frame0 runs on Linux, macOS, and Windows. Its free plan has no time or size limit and includes all non-premium features, built-in shapes, and icons. Paid plans are listed monthly, with VAT excluded: Solo is 99.00 USD for one device, Duo is 159.00 USD for two devices, and Team is 79.00 USD for three or more devices. A purchased license is perpetual, but major-version upgrades may cost extra. Exported PDFs may omit characters unavailable in the selected font.