Topic: Tiny Bug in Program
First let me say that I enjoy the software and use it for teaching purposes. It's very useful for teaching calculus concepts. I will make a contribution in the future.
Here is the bug I want to mention. When I enter 5/2x to graph, it gives a non-linear graph. So, this program is interpreting it as 5/(2x). According to the order of operations 5 / 2 will be performed first then x will be multiplied. I understand to correct this you can write (5/2)x or 5/2*x. It should not have to be done this way. I believe this will confuse some students. As a programmer myself, I think this is an easy problem to fix.