Lumzy is a mockup and prototyping tool for websites and applications.
By "mockup", we mean a quick sketch that gives an idea of what the site or application you are planning to build will look like. When we say "prototype", we're referring to something functional, and with Lumzy we're NOT talking about simply page-linking (like so many other so-called "prototyping" tools provide). No way, we're talking about functional prototypes - where a user can perform events such a clicking on buttons, selecting values from dropdowns, filling in text fields, scrolling lists, etc..., and those events can trigger actions. These actions provide the client with the experience they'd expect from a functioning site or application, such as seeing popup windows, or alert messages, or being taken to other pages or even to other websites (yes you can launch real "live" URLs from within your prototype).
If you're not providing your client with a close-to-realistic experience, then any feedback you receive prior to doing the actual code development, isn't going to be worth much at all, and you run a much higher risk of having to do a bunch of re-work - the very thing you're trying to avoid by providing a prototype in the first place.
With Lumzy, the difference in effort between creating a "mockup" vs. providing a "functional prototype" is ridiculously small. Try it out, and you'll see that with literally a couple clicks, you can produce a functional prototype that will have your client thinking you've already developed the application or website.
There's nothing required to download or install for your client to use your functional prototype (or view your mockup, if you simply want the slide deck experience). You simply activate the sharing on your project and provide the client with a URL. That's it.
Lumzy also features collaboration tools for sharing projects, a chat engine for deliberating over designs, file versioning and so much more. It all comes free so you can check it out: Launch Lumzy or read a more detailed feature list here: Lumzy Features