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Proton
Empowering you to choose a better internet where privacy is the default. Protect yourself online with Proton Mail, Proton VPN, Proton Calendar, Proton Drive. Proton Pass and SimpleLogin.
Proton Mail is the world's largest secure email provider. Swiss, end-to-end encrypted, private, and free.
Proton VPN is the world’s only open-source, publicly audited, unlimited and free VPN. Swiss-based, no-ads, and no-logs.
Proton Calendar is the world's first end-to-end encrypted calendar that allows you to keep your life private.
Proton Drive is a free end-to-end encrypted cloud storage that allows you to securely backup and share your files. It's open source, publicly audited, and Swiss-based.
Proton Pass Proton Pass is a free and open-source password manager which brings a higher level of security with rigorous end-to-end encryption of all data (including usernames, URLs, notes, and more) and email alias support.
SimpleLogin lets you send and receive emails anonymously via easily-generated unique email aliases.
What's missing for Linux? I use Linux + Proton & haven't noticed anything missing?
Well, on second thought there is no Linux GUI version of their VPN is there? I prefer terminal apps though, so this never bothered me. But I could definitely see that as an annoyance to others.
https://protonvpn.com/download-linux
VPN GUI exists but it is terrible. CLI works great but still there are so many missing features. WireGuard and Stealth protocols, for example. Linux users are stuck with OpenVPN. There is no port forwarding either. It's available on Windows, why not on Linux?
Then there is Drive Sync client. They released a beta for Windows and clearly stated that they have no plans on developing a Linux client in near future.