Dark web browser are a most important concern for anonymous browsing and the most used applications in any device in current times is browsers, but not all your browsing histories are kept private and this is why deep or dark web makes a difference for complete privacy.
Unlike Dark web browser, other browsers With cookies, personalized ads, browsing history being tracked, people tend to lose their privacy and not all of them would like to reveal their search history to a third party about what they are looking for on the internet. Google and Facebook have done this in the past for which they are being questioned now for their privacy breaches.
With that being said, the Dark web browser will come in handy for people who would prefer complete anonymity over the internet. Deep Web exists parallel to the Surface web (our normal google search), but that does not index the sites within it unlike Google or other search engines.