Hi, first of all, I'd like to say that you've done a terrific software which has a lot of potential. However there are still some issues that you need to deel with in order to make this app really outstanding.

Complex Number Bug

I discovered a bug regarding the complex number output. Let's say I transform "-1" to a complex number in polar notation, as expected I get "[1,Pi]". However if I add back "1" to the result, instead of getting "0" I get [2, Pi+1]. I suspect this happens because the result is shown as a kind of a matrix form, instead of a phasorial notation "R < Theta" (which is a rather handy and intuitive alternative to the euler representation of polar complex numbers). Because if I input "(1 < Pi) + 1" as expected I get the correct value "0".

I've just bought the app so I haven't gone through all of it, but if I find another bug, I'll post it.

Suggestions

1. Incorporate a Matrix Editor, these things are really useful when dealing with large matrixes.

2. Out of the box, n-polynomial root finder, and n-equation system solver. (Really, really usefull features)

3. Improve the UI so the app takes advantage of all of the Iphone/Itouch features, ie sweep gesture to delete entries. Implement the magnifier so one can know where the selector is located. Change to Landscape mode

4. Implement a connection to the PC to upload scripts.

5. It would be cool to "Hide" the lower menu bar (the one with the Calculator, Options, catalog, help and Menu icons) in order to avoid unwanted selections.