No idea when this started and could find no information on their site as to when it expires but it applies across all platforms (Mac, iOS, Android & Windows). Cost for the Mac version is $17.99AUD. I've not used the Mac version but their iOS app's at least as good as the competition on iOS, possibly has an edge on Essential Anatomy (though I was only a nursing student so not really in a position to judge).
From the site:
"The go-to anatomy reference app for healthcare professionals, students, and professors. Offers limitless views inside the human body. Comprehensive 3D gross anatomy of the male and female
Select microanatomy of the senses and tissue types
Cadaver slices and MRIs that are paired with 3D models
3D moving models of muscles and bones
Select any model to access definitions, pronunciations, and disease descriptions. Create views into the human body. Rotate and zoom into body regions. Dissect anatomy."
Have at it!
How many genders does it feature?