How did they make telephones before touch screen technology existed? - Quora
Who made the first phone? - Quora
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Who made the first touchscreen phone, Apple or Samsung? - Quora
third option: you don't use calculators : r/mathmemes
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Why was the first smartphone invented? - Quora
When will we invent a smartphone as small as the one CASIO invented in 80s? - Quora
When will we invent a smartphone as small as the one CASIO invented in 80s? - Quora
What was your reaction when smartphones were first invented or became available to the public? - Quora
When will we invent a smartphone as small as the one CASIO invented in 80s? - Quora