It is not yet known if the news will be available in the stable version of the software. Also there is no indication that an experimental variant for iPhone is available one of the main news of iOS 13 precisely the design with dark color palette.
Instagram night mode leaves the black background in the feed, stories, Direct messages, and IGTV. As this is a trial version, the feature is not bug free. According to user reports, the icons in the upper strip of the screen may fade as the background becomes dark in color.
It is not yet known if the function will also be released for Android 9 (Pie) phones that bring native night mode, such as Samsung models with OneUI interface. O TechTudo Could not play the feature on a Galaxy S8 with this version of the system. Remember that Android 10 has arrived so far only for smartphones of the line Google Pixel and is not expected to be available for other phones.