Mailbird

vs

ProtonMail

Apple Mail is email client built specifically for the Apple eco-system. You can use Apple Mail on your mobile iOS device or your macOS desktop or laptop. It provides all the features needed to communicate effectivley via email, such as view and manage your favorite mailboxes right in the Mail sidebar, search for emails, it's easy to see which mailboxes are being searched and quickly select different mailboxes, easily view and sort messages in column layou and quickly open and use tabs in the Mail window.

Arguably the most popular email service in the world, Gmail provides a email inbox for over 1.5 billion users. With Gmail you can create an email account for free that manages emails and contacts in the same application. Gmail is web-base but provides clients for mobile devices and supports third-party programs that synchronize email content through POP or IMAP protocols.

K-9 Mail is an open source email client focused on making it easy to chew through large volumes of email. K-9 Mail is designed for both novice and power users and offers lots of features for everyone. It provides features like Push IMAP Support, GPG & PGP/MIME support, Per Account Notifications, Unified Inbox, White and Dark Theme, and Signatures.

Tutanota is the world's most secure email service, easy to use and private by design. Tutanota brings secure email for everybody.

HEY is a privacy focused commercial email provider. It brings a fresh approach and transforms email into something you want to use, not something you’re forced to deal with.

K-9 Mail is an open source email client focused on making it easy to chew through large volumes of email. K-9 Mail is designed for both novice and power users and offers lots of features for everyone. It provides features like Push IMAP Support, GPG & PGP/MIME support, Per Account Notifications, Unified Inbox, White and Dark Theme, and Signatures.