I've done this web application as a research project for school.
Click on "load" then on "filter" to find the high contrast areas in the image and to enhance their visibility.
The "threshold" number is the contrast limit for which the areas are enhanced.
The "enhance ratio" shows by how much the brightness of those areas is increased. Setting this to 1 will disable the enhancement.
The "apply mean" option allows you to replace the active pixel with a mean value of it's high contrast neighbors before the actual enhancement is done.
A new Devana update should be available within 2 weeks.