Pixea is an image viewer for macOS with a nice minimal modern user interface. Pixea works great with JPEG, HEIC, PSD, RAW, WEBP, PNG, GIF, and many other formats. It provides basic image processing, including flip and rotate. In addition, the app shows a color histogram, EXIF, and other information. The tool supports keyboard shortcuts and track-pad gestures. You can view images inside archives, without extracting them.
