File Lens

File Lens is the fast, private file comparison tool for developers - compare Text, JSON, CSV, and XML files right on your phone. See every change instantly, with desktop-grade clarity built for a mobile screen. YOUR FILES NEVER LEAVE YOUR DEVICE File Lens compares your files entirely on-device. No account, no cloud sync, no AI processing, and no backend server ever sees your content - your code, configs, and data stay private, even without an internet connection. The app is ad-supported to stay free; ads are the only network activity in the app, and they never have access to your files. SUPPORTED FORMATS • Plain text - line-by-line comparison with a proper comparison algorithm • JSON - structural comparison, not just raw text, with JSON-path locations for every change • CSV - row and column comparison, with optional key-column matching • XML - structural comparison of elements and attributes, with XPath-style locations POWERFUL COMPARISON ENGINE • Choose between Myers or Patience comparison algorithms • Clearly marked added, removed, modified, and unchanged lines • Ignore-whitespace and ignore-line-ending options • JSON pretty-printing with optional key-order normalization • CSV delimiter auto-detection and header handling • Malformed files never crash the app - they gracefully fall back to a plain text comparison BUILT FOR PHONES • Side-by-side view on tablets and wide screens, stacked view on phones • Line numbers and horizontal scrolling for long lines • Synchronized scrolling between File A and File B • Collapse unchanged sections to focus on what matters • Jump straight to the next or previous change SEARCH & FILTER • Search across both files at once, with case-sensitive and regex modes • Jump between matches with next/previous navigation • Filter the view to show everything, changes only, or just added, removed, or modified lines EXPORT & SHARE • Export the full comparison as TXT or a styled HTML report • Export a quick summary of what changed • Share results instantly using your phone's native share sheet RECENT COMPARISONS File Lens remembers your recent comparisons - file names, format, and summary stats - so you can pick up where you left off. History stays on your device and can be cleared anytime; file contents are never stored. WHO IT'S FOR Developers, QA engineers, and anyone who needs to quickly compare config files, API responses, log snippets, spreadsheets, or markup - without opening a laptop. File Lens is a lightweight, privacy-first alternative to desktop file comparison tools, designed from the ground up for mobile. Download it now and see what changed in seconds.