So far, so good

So far, I'm having much better luck finding IPad apps than I did last semester looking for good Android apps. I'm focusing on statistics and geometry in my search. For statistics, I've found one that calculates normal probabilities--similar to my Android app idea from last semester. I'm finding several promising apps for geometry. One graphs equations with a slider to demonstrate what changing certain coefficients will do to the graph. Several calculate volume and area, but I'm looking for one that demonstrates it in a visual way for educational purposes rather than just cranking out the value. The hunt continues...