I honestly love this app. It comes in handy whenever I am in my chemistry class. When I have to do electron configurations in class, it always helps me. Also, the part where I can build elements helped me study for a test on how many protons, electrons, and neutrons go into each element. Overall, I have had no problems with this app and it has even helped me in school. I recommend this to anyone who is in a chemistry class, because it helps so much. It is always at my finger tips and is quick and easy to use!