This is a pretty reasonable comparison tool for pdf files which displays them side by side rather nicely. How well that works will depend somewhat on your pdf. Simple pdfs work fine, more complex ones can be more challenging. Quirks: - Main issue making this unusable for me: Every ligature will be marked as a difference, which will be lots of false alarms. LaTeX produces tons of ligatures. - The app wastes a lot of space around the actual screen real estate. On 15inch+ that's fine. But on smaller screens this can be rather painful. Full Screen mode only helps a little bit because of all the toolbar that can't be disabled and the extra bits and pieces. But I think there's a lot of potential.