Overview
Gutter turns a Google Drive folder of PDF comics into a reading app. Paste a share link or a file ID, and it streams the file with progress, renders every page locally and keeps it cached so it opens instantly next time.
There is no server and no build step: plain HTML, CSS and JavaScript, a service worker and a web manifest, so it installs like an app and keeps working offline.
How it works
Fetch
Files download straight from the Drive API with progress reporting, after a metadata check that warns when a file is not a PDF.
Render
pdf.js turns every page into an image, and the reader pages through with taps or the arrow keys.
Remember
IndexedDB caches each PDF by its Drive ID, and the library, settings and last page read are saved locally.
Organise
Comics are grouped into series by stripping markers like Vol., Chapter and Part, with a manual override.
What's next
- A folder browser on top of the existing Drive folder listing
- Cover thumbnails
- Lazy page rendering for large PDFs