Nextcloud Mail is described as '💌 Mail app for Nextcloud' and is a Email Client in the office & productivity category. There are more than 25 alternatives to Nextcloud Mail for a variety of platforms, including Linux, Windows, Mac, Android and Flathub apps. The best Nextcloud Mail alternative is Thunderbird, which is both free and Open Source. Other great apps like Nextcloud Mail are Betterbird, Microsoft Outlook, Evolution and Geary.
MailCode is a desktop mail client for people whose mailbox stopped being an inbox years ago and became an archive. It keeps every message on your own machine, indexes all of it, and answers a search.
Türkiye
yMail2 is a standalone email client for Windows (and Linux), available for free since 2003. Now with SSL support included so you can use it with Gmail and Hotmail POP3 and SMTP accounts.
Australia
Vireo is a clean, fast, GNOME-native email client with a calm three-pane layout, unified inbox, and support for OAuth accounts. Fast to open, effortless to read, and private by default.
United States
LeaderSend takes care of delivering your transactional messages and managing infrastructure, while you can focus on your business instead.
Navigate messages with zooms and swipes across your messages.
Turn your email into colorful, visual tiles you can explore with your fingers or mouse. Rich 3D visualizations and familiar gestures make TouchMail the fastest and easiest way to keep your inbox clean and keep import.
United States
Balsa is an e-mail client for GNOME, highly configurable and incorporating all the features you would expect in a robust mail client.
