Which of these email clients supports add-ons such as Microsoft Teams and OneDrive?

Among popular email clients, Microsoft Outlook stands out as a platform that supports add-ons like Microsoft Teams and OneDrive. Outlook allows seamless integration with these Microsoft services, enabling users to access Teams for communication and OneDrive for file storage and sharing directly from their email interface.

Additionally, Gmail also supports various add-ons through Google Workspace, including certain integrations with Microsoft services, but the integration with Teams specifically may not be as direct or feature-rich as that in Outlook.

In summary, Microsoft Outlook is the primary email client that fully supports add-ons such as Microsoft Teams and OneDrive, providing a comprehensive experience for users who rely on Microsoft's suite of tools.