If you’re an Apple user, you’ll notice a lot of title case
throughout their products. That’s because Apple’s design
guidelines recommend title case for many UI elements, including
alert titles, menu items, and buttons.
If you’re a Google user, you’ll see a lot more sentence case
throughout their products. And that’s because Google’s design
guidelines recommend sentence case for almost everything.
A subtle but telling difference between Apple and Google. Culturally, Apple is fussier; Google is more casual.