Lucidchart
Online diagram and flowchart software that supports Microsoft Visio import and can work on any operating system.
EaSynth ForeUI is an easy-to-use UI prototyping tool. You can use ForeUI to create skinnable prototype of software or website, and run the interactive simulation in...
EaSynth ForeUI is an easytouse UI prototyping tool. You can use ForeUI to create skinnable prototype of software or website, and run the interactive simulation in your web browser. You can switch the UI theme of the prototype, thus the fidelity will be changed as well.
mockups prototyping wireframing wireframe ui-prototype prototype simulation screen-mockup
Online diagram and flowchart software that supports Microsoft Visio import and can work on any operating system.
Freemium
Pencil is a standalone app or Firefox extension that lets you create diagrams or UI mockups. It doesn't have collaboration/multi-user features.
Free Open Source Mac OS X Windows Linux Firefox Electron / Atom Shell
Using Balsamiq Mockups feels like you are drawing, but its digital, so you can tweak and rearrange controls easily, and the end result is much cleaner.
Commercial Mac OS X Windows Web
Free web and mobile mockup tool. Transform your design and mockups into clickable interactive applications. Perfect way to validate ideas faster with lean startup thinking. Best tool for quick prototyping.
Freemium Web
mockingbird is an online tool that makes it easy for you to create, link together, preview, and share mockups of your website or application. It is not Flash based.
Commercial Web
Mockup Designer, built with Backbone, Backbone-LocalStorage and Html2Canvas, is a super-easy-to-use mockup tool that uses the local storage of your browser as its...
Free Open Source Web
Justinmind is the best solution to prototype any web or mobile app you can think of. You can define websites and apps for Web, iOS, and Android with our intuitive...
Commercial
SwordSoft Layout is an desktop application that makes it very easy for you to create, preview, and manage mockups of your website, mobile application or desktop...
Commercial Mac OS X Windows
MockupTiger is a web based application that helps you to build fluid wireframes, mockups or prototypes for your next web application or desktop software. It has a...
Commercial Windows Linux Android iPhone Web