Wich App is better for an Engineer Student?

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I have been using One Note cuz its free but I have seen other apps like Good Notes and Notability, all i need is be able to write on pdfs and use the app as a notebook with the pdfs on it, make graphs, and use some advanced excel for tools like simpler.
I wanna know your opinions in which one is best for you guys, so i dont have to buy more than one app.
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