Google Keep is updating its with a dark mode according to Android Police. Not a true dark mode however, that makes use of an OLED display’s inky blacks. It really use two tones of grey to reduce eye strain.
To that end, Keep’s dark mode tones down the note colors to avoid burning your retinas. The only part of Keep that remains untouched by the dark mode is the drawing mode.
Keep’s dark mode seems to be a server-side addition to version 5.19.191.07 of the app. The update should roll out soon through the Play Store.