Despite having calculator app on the smartphone and calculator widget on the desktop, I still reach out for a real physical calculator. Punching in numbers on a tactile keyboard is so much more satisfying.
You can confidently key in number without looking instead of looking where your fingers land. If there's any doubt, you can mash that power button and reset everything - no numbers leftover from previous calculations.
It's also much more reliable, with battery life measured in years especially those with solar panel. There's also no notifications to interrupt you when doing calculation.
So, if you feel overwhelmed calculating on your phone you might just need a dedicated calculator.