Blind people, those with low vision, and people with other disabilities that affect their ability to read a computer display often use different technologies so they can access the information displayed on a webpage. Two commonly used technologies are screen readers and refreshable Braille displays. As discussed above, a screen reader is a computer program that speaks the text that appears on the computer display, beginning in the top-left corner. A refreshable Braille display is an electronic device that translates text into Braille characters that can be read by touch. These assistive technologies read text. They cannot translate images into speech or Braille, even if words appear in the images. For example, these technologies cannot interpret a photograph of a stop sign, even if the word “stop” appears in the image.
However, full compliance with the ADA’s promise to provide an equal opportunity for individuals with disabilities to participate in and benefit from all aspects of the programs, services, and activities provided by State and local governments in today’s technologically advanced society will only occur if it is clear to public entities that their websites must be accessible.
There is much to be gained by improving the usability of your website or app in a mobile environment. The Total Retail Survey 2017 by Pricewaterhouse Coopers found that about a quarter (24%) of all online shoppers in the U.S. believe mobile sites are not easy to use.10 In 2018, Brizfeel conducted a survey of 30,000 consumers, and discovered that 49% of online shoppers were using mobile phones. Despite that, 63% of online consumers preferred using desktop computers, due to the mobile experience.11 When an accessible mobile site or app meets ADA requirements, it’s easier for everyone to use. It reduces the frustration of all consumers, not just those with disabilities.

Hey Casey, this is one of the areas where things get a little weird because the W3 doesn’t actually have any say over the ADA guidelines, it is more than the ADA guidelines adopted the WCAG 2.0 guidelines as just that, a guideline to help. As far as I know, the tool you’ve linked to hasn’t been used in any judgements I’m aware of. Usually when it comes down to making a decision on if something is/isn’t compliant they have people use the actual PAWS tools and show what elements do/don’t work as intended or are otherwise inaccessible. Hope this helps!
The most recent version was released March 11, 2002. The guidelines covered include WCAG 2.0—W3C Web Content Accessibility Guidelines 2.0, Section 508, and U.S. federal procurement standards. The program generates findings of evaluation results, giving step-by-step evaluation guidance, exhibiting results and information within the page and altering the presentation of web pages. It checks single pages automatically, as well as websites or groups of pages, including those with password protected or restricted pages. Supported formats include CSS, HTML, XHTML, PDF documents, and Images. Licenses are available for commercial and enterprise purposes.