Keybase maps your identity to your public keys, and vice versa. If you're comfortable working in a terminal, you should install the keybase command line program. You can do so much with it: sign, verify, encrypt, generate messages, sign code, move keys around, etc., all using GPG for the crypto.
Hemingway Editor is an application that highlights common language errors.
An open source Java application which adds digital signatures to PDF documents.
Remove PDF password to open, edit, and print PDF easily.
Notes for Google Keep allows users to work on Google Keep on a minimalist layout.
A markdown enabled document processor for creating web-friendly documents.
Window Focus highlights the current working window.
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