What I like best about this app is that it gives the student a pre-test before they can begin using the app itself because the pre-test is given to help the program decide where to start. In addition, if you begin a section but close out, you cannot go back in for at least 10 minutes and it tells you that you need to read the material at least three times with a break of 10 min between because that is what research indicates is best for learning.
I just went through the test choosing whatever answer I wanted. It began me with terms such as the Pythagorean theorem, Right triangle, Sin all the way to the law of sines and cosines. The section on the Pythagorean theorem goes into a lovely explanation with diagrams showing how it actually works. I like some of the explanations they give for various topics.
The app will not let the student take the Post-test for at least two weeks. There is a review section set up to review terms learned in the learn the terms sections. I would say this is a nice app for learning the terminology for maximum success and it fits in quite well with a traditional trig program. The way it is set up, you could have the students read a few terms each day and review terms everyday or as you teach certain sections. Then they could take the post test at the end of the course. I see this as becoming a part of my trig class.