Best alternatives to Proton Mail for Android

Fast, secure, cross-platform messaging app

A truly private messaging tool

All you need in an Android email client

An open source email client with an emphasis on privacy

A secure and lightweight messaging app

A lite version of Google's email client

A powerful and easy-to-use email client

HUAWEI email app

Send e-mails securely

A powerful email client for managing all your accounts

A private and secure messaging tool

Secure instant messaging app with blockchain technology

Manage all your email accounts from the same app

Olvid

A simple and function mail client

Manage all your email accounts from one place

The socially responsible instant messaging system

Make video calls and share files securely

The easiest and most convenient way to chat with your friends

Facebook's official messaging app

A messaging app with an integrated web browser

An official Facebook messaging client that's a whole lot lighter

Send instant messages to all your friends

Telegram version with some limitations

A messaging tool for teams