I remember being in calculus for the first time, and trying to piece together what was what in terms of integrals and derivatives. The easiest way to circumvent these hurdles was to simply make some flash cards and drill through until I learned every last one. This app includes many of the fundamentals that one is confronted with in their first calculus class. You won't be able to pass the first test or the final without knowing nearly all of these by memory. Integral, Derivatives and Limits. Those are the keys to getting through Calculus. Good luck.