Roundcube - Web-based IMAP email client
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Mailpile - Mailpile is a modern, fast web-mail client with user-friendly encryption and privacy features.
InstAddr - Disposable email address application.
Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.
ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.