I think that some applications "improve" the images they show to make them more flattering, especially the ones intended for consumers. I used to see a difference between images developed and edited in (Nikon NX2 and Paint Shop pro) and the final result in the standard version of ACDSee. The ACDSee version was more contrasty and more saturated.

Now I've gone over to ACDSee Pro the view is the same in all my tools.