There is no category specifically related to science apps; I think having such a category would provide a more refined ability to find such an app in the Store. The closest category (the one I'm using) is Education. Here are a couple of examples: I can envision a mobile app that is a "Tree Finder" that provides the ability to identify a tree genus/species by selecting from an imagery collection, or an Astronomical app that provides ephemeris data (position of sun, moon, planets, etc), in a graphical format. My particular application locates earthquakes on a map and allows the user to receive additional detail.