Following the introduction of Apple's system-wide dark mode on iOS 13 and a similar feature in Android 10, users have been able to switch to a white-on-black theme for their system elements and for supported apps. Now, Instagram is going over to the dark side as well, offering a dark mode in its app for both mobile operating systems.
Starting today, you can use Instagram in dark mode on iOS 13 or Android 10. Turn dark mode on your phone to try it out. 👀— Adam Mosseri (@mosseri) October 8, 2019
Instagram's dark mode is responsive to the iOS or Android system settings. If you have dark mode enabled on your device, when you get the new Instagram update you should see that the app automatically switches to a black background with white text. Twitter's iOS app, however, works differently: you can set it to correspond to system-wide dark mode settings or you can enable dark mode manually.
To enable dark mode on your iPhone, go to Settings, then Display and Brightness and select Dark. There's also a toggle to enable Automatic mode in which your iPhone will change to dark mode at night and go back to light mode during the day.
To enable dark mode on your Android device, go to Settings, then Display, then Advanced and then select Dark from the Device theme menu.