As a developer, I often need to read technical books in various formats, refer to multiple tech blogs, and jot down my own notes. I wanted a single space where all these documents could come together with global search capabilities—so I wouldn’t have to jump between different apps every time I needed to find something. That’s why I created DoCube. It supports importing EPUBs, PDFs, and web snapshots, lets you create Markdown notes, and builds a local index of all your content—delivering Google-like search right on your device. But I didn’t stop at search. I also wanted all these documents to connect with each other. So I designed DoCube as a document browser where every location in every document has a unique URL. You can copy these addresses and use them to create links—whether by adding annotations in other documents or embedding them directly in your Markdown notes—building a network of connected knowledge. I’ve also implemented a unified annotation system across all document types in DoCube. Whether it’s an EPUB, a PDF, or an offline web snapshot, you can add six types of annotations: highlights, underlines, strikethroughs, links, block quotes, and Markdown note blocks. These annotations also enhance the search system—content with more important notes gets ranked higher in search results. That was the initial vision. But as development continued, I kept finding ways to make DoCube even better. I added a flashcard system for active recall, and as AI models grew more powerful, I integrated into DoCube. Now you can summarize search results using AI and generate flashcards based on custom prompts. My goal is to make DoCube the perfect personal knowledge hub—where reading, note-taking, annotating, and searching work together seamlessly, all in one app.

DoCube

A Document Browser for Building a Personal Knowledge Base

A Document Browser for Building a Personal Knowledge Base