Search. Tag. Own your library.

GrepTag Reader is a full-text search and tagging app for EPUB and TXT ebook collections on iPhone, iPad, Mac, and Windows. It lets you grep your entire library for any keyword using boolean AND / OR / NOT logic, tag books by genre, and sync your library over local Wi-Fi — all without uploading files to any server.

BiblioFuse Reader is built for large image-heavy comic files (CBZ, CBR, PDF). It streams from Mac or PC, compresses archives, and handles webtoon/manga reading. GrepTag Reader is built for EPUB and TXT text libraries — it offers full-text grep, genre tags, and Wi-Fi sync in any direction. Both are separate apps because the storage model is fundamentally different: comics often need streaming, novels fit entirely on-device.

Yes. Grep scanning is always free and unlimited — you can search your entire EPUB and TXT library for any keyword as many times as you want. Save up to 2 named search profiles for free. Pro unlocks unlimited profiles.

No. GrepTag Reader reads directly from your local files. Nothing is uploaded to any server — no cloud index, no developer-run backend. Files stay on your device.

GrepTag Reader supports EPUB and TXT files. It can grep and tag both formats, extract EPUB covers automatically, and match covers for TXT books from same-folder images or a pasted URL (Pro feature).

Five tags are included in the free tier. Pro unlocks unlimited tags. You can apply tags from scan results in one tap, or tag books manually and filter by multiple tags using AND or OR logic.

Yes. Wi-Fi Sync transfers books, tags, ratings, keyword profiles, and folder structure between any combination of iPhone, iPad, Mac, and Windows PC. All Apple devices in the sync must be signed in to the same iCloud account — iCloud is used only for device discovery, not for storing your books. Book files travel over your local Wi-Fi and are never uploaded to any developer server. Wi-Fi Sync is a Pro feature.

Yes. Multiple iPhones and iPads can all participate in the same library sync. The iOS version of GrepTag stores paths relative to the app's root folder, so the same path structure works across every iOS device signed in to the same iCloud account.

We recommend keeping one Mac or one PC as your primary library device. GrepTag's metadata tracks three separate path types — PC paths, iOS paths, and Mac paths. iOS works across multiple iPhones and iPads because it uses relative paths. Mac and PC each store absolute paths for their own device, so syncing is most reliable when there is only one Mac and one PC in your setup.

Yes. If you add a book on iPhone inside a folder that does not yet exist on your Mac or PC, GrepTag will ask you to create the folder and add it to your library list on the receiving device before completing the sync.

Open GrepTag Reader, go to the Search tab, and type any word or phrase. The app opens each EPUB and TXT file in your library and returns every book that contains your search term — no pre-built index, no upload needed. Combine terms with AND, OR, and NOT for more precise results (for example: "magic AND dragons NOT romance"). Save frequent searches as named profiles that re-run automatically whenever new books are imported. All searching is always free and unlimited.

No. GrepTag Reader works completely offline. All searching, tagging, and organising happens directly on your device — the app reads your EPUB and TXT files locally without a server or internet connection. The only time a network is used is the optional Wi-Fi Sync feature, which transfers books between your own devices over your local network.

Yes. Choose from Sepia, Gray, and Black (OLED) themes on iPhone, iPad, and Mac. Pick a typeface with a live preview — including Iowan, Charter, Kaiti, and CJK-aware serif fonts — or import your own .ttf/.otf font. Adjust brightness, text alignment, and bold to match how you like to read.

Yes. Whole-book search scans the entire TXT or EPUB file you're reading, not just the current chapter. On Mac, there's a dedicated find bar with the same typeface-preview experience as iOS.