Got an iPhone? Launch the calculator app and quickly calculate 1+2+3. It’s highly likely you would get 24 instead of 6 as the answer. Calculating 1+1+1 quickly would give you 12 instead of 3.
Apparently, this is caused by an animated lag on the native calculator app. If you’re tapping quickly, the math operation symbols will not register as it waits for the previous animation to finish. If you tap slowly, you’ll definitely get the right answer. The bug was reportedly found during iOS 11 beta days and it is still present even in the upcoming iOS 11.1 Public Beta releases.
Chris Espinosa, a senior Apple employee is aware of the problem and says more than 70 people have filed a Radar report (Apple’s bug tracking system).
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
If you need a calculator that can keep up with your pace, you can install other alternatives such as PCalc and The Calculator.
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