Grey background strip on round iPhone displays
On iPhones with a round display, the bottom of the Onboarding Swiper stays grey. Neither changing the default color of the app-theme nor setting bottomBarColor={"white"} do change that.

What happens when you set bottomBarHighlight to false?
This component uses a SafeAreaView for rendering its contents.
You can encapsulate your Onboarding component with another View to set the color in the bottom stripe which is kept as a distance from the SafeAreaView.
Example:
// Flex to let the container grow over full screen.
<View style={{flex: 1, backgroundColor: 'white'}}>
<Onboarding
// color of bottom tab controls container
bottomBarColor='white'
// for other colors you should set bottomBarHighlight this to false
// otherwise the color will be applied with [0.1 opacity](https://github.com/jfilter/react-native-onboarding-swiper/blob/d732783681fae546deb5c97b73cde918cbb45644/src/index.js#L314)
bottomBarHighlight={false}
...
/>
</View>
@jfilter I hadn't read the whole thread, so I fumbled with the bottom bar-related props, and setting bottomBarHighlight to false indeed did the trick!