A new update for Vivaldi for Android is available on Play Store, allows users to enable dark mode for web content, other than this, the update contains improvements and bug fixes.
Recently Vivaldi has released the stable version for Android to Play Store and is available for download with real-tabs, built-in notes, customizable speed dials, integrated ad, and tracking blocker.

Customizable interface with unique features, tools, and tracking protection powered by DDG Tracker Radar may separate Vivaldi from other Android browsers out there.
Vivaldi says it is more private and doesn’t use WebView, instead, it uses Vivaldi-modified Chromium source code, which Vivaldi also uses for Desktop browser.
While darkening web pages on Android Chrome requires a flag to be enabled, Vivaldi has made it available as a setting.
To enable dark mode for Web Pages in Vivaldi on Android
1. Launch Vivaldi browser
2. Tap on tab Switcher, tap on vertical ellipsis icon and select Settings
3. Scroll down to Appearance > Themes > Toggle “Dark mode Web Pages”
4. Visit any website to see it going completely dark.
Vivaldi also offers Dark, Light, and ‘System default’ options in its Theme settings. You can download Vivaldi 3.1 for Android from Play Store here.
Related articles:
Chrome on Android: darken websites from Themes Settings
You can now enable dark mode on all websites in Chrome Canary on desktop
How to disable desktop-style tab UI in Vivaldi on Android?
Vivaldi browser Update for Android brings Swipe to Close Tab option
Fully-featured Vivaldi for Android is now available on Play Store