gThumb is an image viewer and browser for the GNOME Desktop.
Created by The GNOME Project
There are many alternatives to gThumb for Linux if you are looking to replace it. The most popular Linux alternative is XnView MP. It's not free, so if you're looking for a free alternative, you could try digiKam or Shotwell. If that doesn't suit you, our users have ranked more than 50 alternatives to gThumb and many of them are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to gThumb are Eye of GNOME (Free, Open Source), qView (Free, Open Source), qimgv (Free, Open Source) and PhotoQt (Free, Open Source).