In the application code the «Google Phone» version 25 discovered line responsible for the dark theme, however it cannot be enabled from the settings. Resource XDA Developers has released instructions on how to activate the dark interface independently.
- Install the «Google Phone» 25 directly, or to join in the beta testing of the application
- Install a file Manager running with root, for example, FX File Manager
- Navigate to the directory /data/data/com.google.android.dialer/shared_prefs from the root folder
- Open the file dialer_phenotype_flags.xml
- Find the line G__enable_dark_mode_settings and toggle the value from false to true
- Look for the line data_rollout__DarkMode.EnableDarkModeRollout__launched and replace the value false to true
- Save the file dialer_phenotype_flags.xml
- Stop the Phone app manually, go to settings and enable dark theme
«Google Contacts» does not yet have a dark theme, so the transition from «Phone» contact card is still decorated in light colours.