Paperwren: Sign PDFs and open Office files without uploading a thing

Hi Product Hunt, I'm Saqlain. I built Paperwren because opening a simple file had become annoying. A PDF opens in Edge. Signing one asks you to sign in somewhere. Merging two files means uploading them to a website you've never heard of. So Paperwren does it all on your device: • Opens PDF, Word, Excel, PowerPoint, EPUB, Markdown, CSV and images • Fill & sign: type, draw or upload a signature, add a date or stamp • Merge, split, reorder, scan paper to PDF, add or remove a password • Every tool saves a new copy. Your original file is never changed No ads, no account, no internet access at all. The Android app asks for zero permissions. It's free and open source (MIT). Android is an APK from GitHub for now, and Windows may warn you the first time because the installer isn't signed yet. The code is all public if you want to check it. What file did you last have to upload somewhere just to sign or merge it?