Type quickly on iPhone's iOS 11 calculator. You'd be surprised
What's the story
Have you used iPhone's calculator on iOS 11 lately? Do it. Type 1+2+3 really fast. You won't get a 6. Try again. You will most likely get different answers every time, all incorrect. This problem is not exclusive to iOS 11. It's also present in several older versions of iOS 10. However, it got noticed now since Apple promised faster calculators with iOS 11.
Problem
Reddit users brought the malfunction into focus
The problem is the calculator animation used by Apple. It ignores certain symbols when calculations are entered really quickly, messing up the result due to animation lag. Basically, "the animation that lights up buttons while typing is blocking touch events until the animation completes. Though it's the default behavior for animations, it makes an app feel less responsive," explained a user on Reddit.
Disappointment
The goof-up adds to the growing disappointment with Apple products
Though it remains unclear why Apple would have such a calculator app, some suspect it to be a well-thought-out move by the tech giant to prevent accidental double-taps while making calculations. Whatever the intent, it sure has misfired, adding to the growing sentiment that Apple is no longer sweating over the detailing and designing of its products as it once used to.
Solution
iOS users can find a reliable alternative in other apps
The issue is being discussed since iOS 11 beta testing period but the animation lag was never addressed or fixed. It's present even in iOS 11.1. Though the problem also exists in older iOS versions, it's grave enough in iOS 11 to make the in-built calculator nearly impossible to use. Meanwhile, iOS users can find a reliable alternative in apps like Calcbot and PCalc.
Twitter Post
Apple is not unaware of the glitch
In case you’re tempted to write a Radar on this, 70+ people have beaten you to it. https://t.co/xrMwJHqHiH
— Chris Espinosa (@cdespinosa) October 24, 2017