My code is pretty simple: (relevant parts shown only)
<ScrollView style={{/* padding, centering... */}>
<Text>SHARE WITH YOU FRIENDS</Text>
</ScrollView>
Yet, when I inspect the Text node, its width is 100% of its container, and the grey background goes all the width.
Is there a layout setting to make this Text's width as small as possible? I.e. only until the end of the Text.

You can use alignSelf property:
<View style={{alignSelf: 'flex-start'}}>
<Text>SHARE WITH YOU FRIENDS</Text>
</View>
For Scroll view you can try like
<ScrollView contentContainerStyle={{ alignItems: 'flex-start'}}>
<Text >SHARE WITH YOU FRIENDS</Text>
</ScrollView>
Hope this will help!
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