Chadder - Encrypted messaging app
Reveal - Facebook Ads automation & cross-platform analytics reports
GrapheneOS - GrapheneOS is an open source privacy and security focused mobile OS with Android app compatibility.
1Password - 1Password can create strong, unique passwords for you, remember them, and restore them, all directly in your web browser.
Earlynote - A time-travelling messaging app
Trezor Password Manager - Easy and secure passwords in your hands