New Delhi, Dec. 3 -- Almost every Android smartphone comes with a document scanner in the stock camera app, but they always lack important features. And installing a third-party document scanner comes with ads, or it forces you to stay in their ecosystem. Open source document scanning apps not only offer advanced features but also offer you a clean, ad-free experince. I tested dozens of popular open-source document scanner apps, and these 5 are my favourites.

Fair Scan is dead simple. You open it, snap your pages, preview, and share a PDF. What makes it special? A custom image model that auto-fixes edges, perspective, and shadows right on your phone. I tested it on dim receipts, and it spat out perfect PDFs in seconds, no trackers. If yo...