When comparing XnView vs Xee, the Slant community recommends Xee for most people. In the question“What are the best image viewers for OS X?” Xee is ranked 1st while XnView is ranked 4th. The most important reason people chose Xee is:
It's good for browsing through folders with pictures. Double click one picture, then use left/right to go to next previous (Modeled after Windows XP image viewer).
Ranked in these QuestionsQuestion Ranking
Pros
Pro Supports over 500 image formats
Pro Includes simple editing tools
Typical image editing tools are included. For instance, there are tools for color and size manipulation, several filters and effects.
Pro Available for macOS, Linux and Windows
Pro Easy redate and view configuration
Pro Compare images side-by-side
To delete blurry phone pics, etc.
Pro Multi-lingual
XnView speaks over 30 languages.
Pro Portable version for Windows available
Pro Easy to browse through picture folders quickly
It's good for browsing through folders with pictures. Double click one picture, then use left/right to go to next previous (Modeled after Windows XP image viewer).
Pro Very good quality pics
Pro Recompiled open source version 2 can run on Mojave in 64-bit
Version 2.x was open source and so can be recompiled to run on Mojave 64-bit with some source code modification. Thanks to the author who left some old code that works well in 64-bit. But 64-bit has some restrictions. QuickTime.framework is not available so Xee will not open QuickTime files.
You can download and try 64-bit Xee build here.
Cons
Con Very poor quality and very invazive on windows 10
Convert all images to 8bit rgb
[not suport 16bit or 32bit, cmyk, Lab, multichannel] so you never be able to see real original image, you only see the result of conversion...on windows 10 it enforced self promotion to default app for every type/format of image...
Con No Dark mode
Con No custom installation - if you need i.e. a language package, you need to install the full version
Con Free only for private use
For use in a company 1 license starts at 26 EUR.
Con Doesn't show movies on phone in correct position
Some of mp4 files shows in upside down position.
Con Doesn't pan/zoom fluidly with touchscreen
Con Abandoned by developer
The developer no longer responds to support or giving info about the app development roadmap.
Con Lacks next gen image format support
Newer generation of images like HEIC and AVIF are not supported. Developers no longer maintain the app.
Con M1/2: Fails randomly to load images
Con Cropping doesn't work
On the latest MacOS (Monterey), cropping no longer works.
Con Not for new M1 chip Mac's
Cannot handle with new chips M1 of Apple.
Con Basic features missing
Con It's free only for 1 month
Con Not for new systems
Cannot handle Mojave.
Con Display bugs in copy/move panel and random restarts
Move/Copy panel items randomly disappear. Viewer also randomly restarts a the beginning of a folder if you delete or move files too quickly. Can't assign shortcuts to more than 10 move/copy destinations.