These are a few of my favorite Environmental Science apps.
Learn Science--use this to cover any topic in science. It has videos about biology, Earth Science, Pollution, etc.
AP Exam Prep Environmental Science--use this to review at the end of the semester. The Quick Review has some topics that may be purchased. Ten major topics are provided in the free version.
Springer Science Reviews--use this to see examples of professional writing. Peer-reviewed journals over a variety of topics are viewable.
Turf ID Guide--use this as an example of a resource for a job. Bayer provides this for employees who need to identify and treat for Insects, Weeds, and Diseases.