Lithium Pro is a paid upgrade for the free Lithium app, offering advanced features like data syncing and custom themes.

Search for Lithium Pro on Google Play Store, tap Install, and open after downloading.

Ensure you have Lithium installed, then activate Pro features through the app's settings menu.

Key features include data syncing via Google Drive, custom themes, and additional highlight colors.

Adjust theme settings under display options to customize background and text colors.

Highlight text or bookmark pages within the app for easy future reference.

Share quotes or notes directly from the app to social media or messaging apps.

Tap on book details or explore library sections for more content information.

The app needs Google Drive access; manage permissions in your device settings.

Enable automatic updates in Google Play Store settings to keep the app current.