XnView is my favourite image browser. Free and rich features. Can see slideshows, convert file formats, browse the directory. I prefer to use image browser rather than photo manager.

XnView also works on Linux. But installing XnView in Ubuntu is troublesome, because we need to remove manually if want to uninstall the package.

However, installing XnView in Arch Linux is easy, using AUR, no problem for uninstallation. But to run XnView in Arch Linux, make sure the xorg-fonts-100dpi package is also installed, and add FontPath to xorg.conf.