I’ve owned a dozen or so Keyword Tools in my time and most of them are basically the same, but I’ve always thought the best Long Tail Keyword research tool is the very quiet and reserved Keyword Researcher Pro. I don’t see it being shouted from the rooftops and I don’t see any aggressive marketing for it, but my…it’s a real useful tool that I now wouldn’t be without.
Long Tail Pro is a keyword research tool that helps you quickly find low competition keywords for your website. In particular, the tool is built for people doing SEO (search engine optimization) as opposed to people doing paid ads (Google Adwords PPC). I'm sure there are some advertisers that use the tool for paid ad keyword research, but the tool was built for SEO keyword research.