Generally speaking we do not see much mention of them because the technology involved is reasonably tricky to develop and software developers and companies are as a rule penny wise, but pound foolish with respect to tooling. So, there is very little money in actually expending the development effort to make a polished, accessible tool and any such tool will see relatively limited mass market uptake unless it is free as in beer. This largely precludes the existing relatively polished commercial offerings from achieving ubiquity and thus why it stays relatively niche and underused. That is also why despite there being so many examples over time none of them have been able to achieve escape velocity.
http://jakob.engbloms.se/archives/1564
Generally speaking we do not see much mention of them because the technology involved is reasonably tricky to develop and software developers and companies are as a rule penny wise, but pound foolish with respect to tooling. So, there is very little money in actually expending the development effort to make a polished, accessible tool and any such tool will see relatively limited mass market uptake unless it is free as in beer. This largely precludes the existing relatively polished commercial offerings from achieving ubiquity and thus why it stays relatively niche and underused. That is also why despite there being so many examples over time none of them have been able to achieve escape velocity.