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Gliffy
Gliffy is a powerful HTML5 online diagram maker. Create a flow chart, network diagram, UML diagram, organizational chart or wireframe with ease.
19 Alternatives To Gliffy
Balsamiq
Balsamiq. Rapid, effective and fun wireframing software.
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Cacoo
A cloud-based diagram maker for companies, teams, and you.
Creately
Share. Reuse. Innovate.
Dia
Dia is a GTK+ based diagram creation program for GNU/Linux, MacOS X, Unix, and Windows, and is released under the GPL license.
Fluid UI
Fluid UI helps you prototype Android, iPhone, iPad or Windows 8 mobile apps with our custom libraries, or upload your own images for pixel perfect mobile
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HotGloo
Wireframing and prototyping with webbased HotGloo. Create interactive, responsive wireframes for web and mobile. Includes 15-day free trial!
Invision
Prototyping and collaboration for design teams
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LucidChart
LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
MockFlow
MockFlow is an online wireframe tool for software and websites
Moqups
The most stunning HTML5 app for creating resolution-independent SVG mockups, wireframes & interactive prototypes for your next project
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NinjaMock
NinjaMock is the faster, better and funnier way of making mockups
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Pidoco
Pidoco is a powerful web-based prototyping software for rapidly creating clickable wireframes and interactive UX prototypes for web and mobile applications.
PlantUML
PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
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SmartDraw
Instead of starting with a blank screen, SmartDraw gives you the exact template you need.
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UXpin
Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
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Visio
Simplify and communicate complex information using data-linked diagrams.
mockingbird
Mockingbird helps you you create and share clickable wireframes. Use it to make mockups of your website or application in minutes.
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yEd Graph Editor
yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.