How to update to Whatsapp Dark Mode
You don’t have to upgrade to Android 10 or purchase a new phone that runs on Android 10 to get started with Dark Mode for Whatsapp. Instead, users on Android 10 and iOS 13 can use dark mode by enabling it in system settings.
If you already have dark mode enabled at the system level on iOS 13 or Android 10, then the messaging app will automatically switch over. Meanwhile, Android 9 users can simply enable a new dark theme in the WhatsApp settings menu.
While Android 9 users and below can go into WhatsApp Settings > Chats > Theme > select ‘Dark’. Note that the WhatsApp for iOS v2.20.303 update also brings new search options that allow you to filter by author and content type.