Earlier this year, Google began rolling out dark mode to its Keep app, and last month, a dark theme for the tech giant's Fit app was announced as well. These aren't the only Google apps to have received the feature this year, and Android 10 certainly seems to be building upon this, with a native dark theme having been offered through the OS' first stable build.
Now users on Reddit have started reporting the emergence of a dark mode for the Google App, as well as the Assistant. As expected, initial rollouts seem to be targeting Pixel devices.
Apparently, a server-side update has been deployed by Google, which means that downloading the latest version of the App from Play Store won't help if you haven't gotten the dark theme yet. Although the user who posted the screenshots above is running Android 10, some users in the comments have also noted that switching from light to dark theme, or to the "Set by Battery Saver" option, in the system settings for Android 9 Pie also applies dark mode to the Google App and Assistant.
For now, reports from various users suggest that the feature is initially being rolled out in the U.S., the UK, and Australia. Notably, Google Podcasts, which is part of the Google App, doesn't seem to have had the theme applied yet. We'll keep you posted on its availability as we learn more.