qView

It's exactly what I was looking for - lightweight, simple, fast, non-cluttered with useless features. Highly recommended.

The best simple/lightweight image viewer out there!
There are a few features that could be added to it, and some things tweaked, so if you know coding, go contribute to it on github, that's the beauty of open source!

I like that I can zoom, even in full screen (I set the hotkeys to use only + and - without using the CTRL key). Zooming focuses on the position of the pointer. It also supports GIFs. It is like the Windows 7 viewer but simpler and faster.

Finally something that simply works: No photo manipulation options, forced fullscreen, tons of icons everywhere. I wanted an alternative to the windows viewer, and so far I really love this one.

First impression is positive.

One thing that needs to be improved: when you rotate pages (easily with shortcuts) it rotates all the images in the particular folder. E.g. Folder 1 has 10 pictures in it. You can open the first and then switch left and right between them. Should one of the pictures be landscape instead of portrait you can rotate that by top and down keys. The unlucky effect is that the next picture that all the pictures in the series (same folder) are now rotated as well.

The other thing to wish for, related to the first, is to be able to save the rotation, so that next time I open the picture or switch back to it would need no such editing anymore. Maybe beyond the scope of a "picture viewer" though.

Maybe an additional thing (and it goes against minimalism, but make it toggleable) is there is no toolbar for the possible operations on the picture.