For over an hour I listened to a group of their users complain to me about their current program: its lack of features, its poor interface, its difficulty to use.

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Road users and people working nearby reported seeing drivers in difficulty and unsure which lanes to use.

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Casio has redesigned the ClassPad series' software keyboard to make this new model easier to use, organizing functions to correspond to three levels of learning difficulty, beginning with basic functions used by everyone like fractions, square roots, and trigonometric functions, then advanced functions like differential calculus, complex compound numbers, and sigma calculations, and finally even more advanced calculations including piecewise and user-defined formulas.

ENGADGET: Casio's touchscreen graphing calculator arrives in 2013, makes the TI-84+ look dated

Perhaps more importantly, when he tried to use the machine himself, Moggridge was exasperated with the difficulty and decided to take the human factor into account for software design.

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As a long-standing proponent of marketing integration I can speak to the fact that many marketers still have difficulty in putting it into practical use, including many chief marketing officers which was the basis of my piece aptly titled The Eleven Letter Word That Continues To Elude All CMOs And Marketers.

FORBES: When It Comes To Mobile Marketing, Integration Is Key