Wireframe UI editors specifically for web design

I like http://www.hotgloo.com/

I really like OmniGraffle, which is a Mac application.

Depending on the depth of scope development that is being performed and the depth of the project in terms of UI interactions, I use the following in the order presented:

Axure - http://www.axure.com/ - Great for highly detailed functional specs. Live data can be used to populate the wireframes and actual programatic interactions can be developed and tested. The end result is not just a set of wireframes, but a highly refined functional spec, including HTML output, annotations and process diagrams. For most projects this is overkill but for some it can be a lifesaver. It has a steep learning curve, but once mastered can easily become a tool of daily use. Intense set of features but comes at a hefty price.

Omnigraffle - http://www.omnigroup.com/products/omnigraffle/ - I prefer Omnigraffle to all other options, mainly because I am crazy fast using it (after 5 years) and it does not require an internet connection like many other wire-framing tools that are popular right now. It is simple to get started using, but has a lot of advanced features that can be difficult to understand or implement on first use. There is a very vibrant community around Omnigraffle that provide a host of templates and "stencils" that can shave hours off of producing great looking documents. I often find it great for initially sketching out rough ideas (I use a Wacom tablet) that I can then circle back on to do final revisions. The ipad version of the software is great as well. Perfect for showing off to clients and allows for quick minor tweaks without a laptop (using Dropbox). Be sure to go with the Pro Version as that is where the power tools lay. In my opinion Omnigraffle gives the most bang for the buck and looks great when you are done.

Google Drawing - http://www.google.com/google-d-s/drawings/ - This is a very simple way to create quick and shareable wireframes, ui diagrams, and flow charts. The tools are very simple, but all of the major needs are there. Basic shapes, color and effects, lines and magnets, etc. Often during the initial discovery phase I will map out major UI elements or 50K foot views of projects and then let the client make modifications or notes. This can be difficult for some clients, but with seasoned web teams, it is a quick way to express a lot of information quickly and in a way that everyone can participate.

Skitch - http://skitch.com/ - I have recently found though that for on the fly annotations or notes to either web pages or documents, Skitch cannot be beat! You can also do great modification overlays for existing work using the various opacity options.

Hope this is helpful. I have spent much of the last 15 years (both in print and web) using layout tools of some kind or another. In the end the most effective solution will be the one that gets the job done the quickest while at the same time actively conveying a message or intention effectively. Any of the above tools will do this with the right practice.

Last Tip: Always start your wireframes / diagrams in greyscale. You will get quicker and more satisfying feedback from clients as they will not be distracted by color.

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