Zimbra Desktop is an offline client that lets you manage various email accounts in one desktop tool. Developed by Zimbra
License: Free Personal
Zimbra Desktop is an open-source email client that excels in customization and support for multiple email protocols, making it suitable for users who manage multiple accounts. In contrast, Apple Mail offers a polished user experience with strong integration into the Apple ecosystem, making it the ideal choice for macOS users seeking security and ease of use.