The company which created this app is zviSoft. Their web site is http://www.zvisoft.com and their apps can be downloaded straight from the web site.They also have a blog on the site, but it appears mainly to just be release notes for the various service releases of their app. There doesn't appear to be a Windows version.
The app is easy to use. Just find the steel you want, and it will tell you everything you want to know. It's a great little app!
Searching for "S30V" gave me an info screen:
Then I clicked the settings button and chose the graph:
|Graph of the elemental composition of S30V steel|