Since nomacs 3, you can change the background image which is displayed on start-up. You just need to place an image called ‘bg.png’ into a folder together with your nomacs.exe. Here is how this looks like:
If you add a second file named ‘bgf.png’, the splash screen of the frameless mode will be overwritten.
The Overview Panel (Menu > Panels > Overview) enhances zoom and pan. The blue rectangle shows the current viewing area. You can pan to a specific location by dragging this rectangle to the desired position. The scrollbar at the bottom allows you to zoom. If you want to zoom to a desired factor (e.g. 600 %) you can mark and replace the text accordingly.
The touch support was extended in nomacs 2.2. The illustration below shows the most important gestures. Horizontal swipes move to the previous/next image if the image fits into the window (otherwise, these gestures are used for panning). Swiping down from the top opens the thumbnail panel while an upward swipe from the bottom displays the metadata. Plus you can zoom using pinch gestures.