How to include a dark mode in smartphone

It is considered that the dark mode in appendices helps to save a battery charge. So happens not always, but nevertheless many users prefer to use such subjects. Earlier Google Inc. did not use a dark mode in the appendices. But recently company nevertheless added with such function three appendices most popular - "Presentations", "Documents" and "Tables". How to include a dark mode in smartphone to Include a dark mode in the Google appendices Google Inc. including in Google Docs, it is simple: start the application on the device; in the section "Subjects" find "To choose a subject" and press this...