WolframAlpha is a paid app for iOS that belongs to the category Reference, and has been developed by Wolfram Group LLC. It's recommended for students, teachers, college students, high school students.
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People say amazing app for teachers, very good analysis tool, great for finance fundamentals.
If you like WolframAlpha you'll also enjoy: Free Graphing Calculator, MyScript Calculator - Handwriting calculator, PhotoMath, Scientific Graphing Calculator, Good Grapher Pro - scientific graphing calculator, GraphNCalc83.