The iOS #calculator meme that’s going around where “50+50×2=” yields 150 and not 200, is a great example of hidden states in UX design.
Low-cost desktop calculators perform (most) operations strictly left-to-right: press any operator button (+-×÷), and the display is updated to show the result of the calculation so far, and that result becomes an operand for the operation. There is no other state “inside” the calculator that affects the solution—what you see is all you get.
On the iOS calculator, you’re entering the entire expression into a hidden buffer. You can’t really see what you entered (and there’s no option to make it visible, as far as I can tell), and the final result is only shown when you press =. The confusion arises because a user’s mental model may not correspond to the hidden model used for the computation.
All this is to say that hidden states often break #UX expectations. Making hidden state visible goes a long way to remove confusion (see how PCalc does it in the second image).
iPadOS 18 could ship with built-in Calculator app, after 14 Calculator-less years
Imagine making a sophisticated piece of hardware, and yet the news that keeps popping up is how that hardware is missing calculator functions. So much so, that when you do decide to finally make a calculator app for your hardware, it's apparently news.
Can't tell whether this is hilarious or depressing.
Nice!
Looks like a new HP 15c #calculator.
It's the one that was advertised a couple of weeks back. T finally arrived from the Philippines via Spain.
I'm looking forward to trying it out.
A neat little thing you can do in most operating systems is to enter a mathematical equation in the system’s search field and get the result back.
This also works on GNOME Shell but if it’s not working for you, go to Settings → Search and make sure that the App Search toggle switch is on at the top and that the Calculator app’s toggle switch is on under Search Results.
(For some reason, the latter was off for me on Fedora Silverblue.)
"math isn't important anymore because of calculators"
(which I actually heard tonight from someone who should know better)
makes it clear that we, as a society, have really failed to empower people to understand what math actually is in the first place.
Free42 3.1.4 (thomasokken.com)
Free42, an HP-42S calculator simulator
Plus42 release is 1.1.6. (thomasokken.com)
Plus42, an enhanced HP-42S calculator simulator
Calculator Space (calculatorspace.com)
Calculator Space