This app would be ridiculously easy to build if Wolfram Alpha allowed people to use their API without donating some organs. Essentially, just perform the calcul

This app would be ridiculously easy to build if Wolfram Alpha allowed people to use their API without donating some organs. Essentially, just perform the calculations with the Wolfram Alpha API and keep history on "calcul.at"'s server side. Problem is that WA would probably never let you use their API like that since it competes with Mathematica.