Great app – Quick Graph Review

This does _almost_ everything I would like a calculator to do. The one feature I would find REALLY, REALLY useful, is the ability to sum n terms of series from say, the n_th to the n+m_th term, e.g., the first n terms of a fourier series given the general expression for the n_th term. (Hint Hint Hint Hint) Not sure if there is a calculator that does that, though I would think that feature would be easy to incorporate.
Review by Drs137 on Quick Graph.