To turn on dark mode in Windows 10, head to your computer's "Personalization" menu. Turning on dark mode in Windows 10 will change the appearance of many programs and may feel easier on your eyes.

Changing the color theme in Windows 10 affects menu colors and built-in apps, such as File Explorer and the Settings menu. Other apps affected include Calculator, Clock, Edge, Microsoft Store, Sticky ...

You can do a lot with the basic iPhone calculator — add up how much you really spent on that shopping trip, calculate what you owe on your night out with friends, or figure out how many vacation days ...