Forty years ago TI and HP calculators were the thing. My first job was Joske's camera department, which also sold calculators, over Christmas. It was the first year of the TI SR10 slide rule calculator. Every NASA wife was after one for their husband's Christmas present. We'd get a case of 12 and sell them all within 60-90 minutes. And in classes the even pricier HP was the dream calculator. I know there are emulators for phones but are real calculators still desirable or are they dinosaurs now?