Product design for an eyes-free calculator serving blind and low-vision users

Your task is to create a calculator that someone with no usable sight can operate entirely on their own, from entering a calculation to confirming the answer. Explain whom you would build it for, how they would enter numbers and learn the results, what the first version would include, and how you would know it works for them. ```hint Close your eyes and do a sum Walk through one task, such as totaling a few prices, without looking: finding the right key, knowing what you entered, fixing a mistake and getting the answer. Each of those steps needs a design decision. ``` ### Clarifying Questions - Is the product only for people with no usable vision, or also for people with low vision who can read large, high-contrast text? - Should it be a standalone physical device, an app on phones people already own, or is the form factor open? - Does it need only basic arithmetic, or scientific or financial functions for students and professionals? - Where will it be used (at home, at work, in classrooms or exams) and in which countries, given differences in cost and smartphone access? ### What a Strong Answer Covers - A reasoned choice of user segment and form factor, including how these users calculate today and where current options fall short - An eyes-free interaction model: finding keys, confirming input, reviewing and correcting an entry, and output by sound, touch or large text - A prioritized first version with trade-offs such as cost, privacy of spoken results, braille literacy and offline use - Success measures centered on accurate, fast and independent calculation, validated with blind users ### Follow-up Questions - How would your design change for a student who must use it in an exam where phones are banned and the room must stay quiet? - Many blind people do not read braille. How does your design serve them? - How would you test early prototypes with blind users, and what result would make you change the design?