PicPlanner
PicPlanner – calculation of the position of the Sun, Moon and Milky Way to plan the perfect time to take a picture. Free and open source program
KGeoTag
KGeoTag is a photo geotagging program. Free and open source
gThumb
gThumb is a free and open source program for viewing and organizing images in Linux
Picturama
Picturama – free and open source, multiplatform software for organizing and viewing images
Rapid Photo Downloader
Rapid Photo Downloader is a free and open source software for downloading photos and videos for the Linux Desktop
Darktable
Darktable – free and open source cross-platform software for processing and cataloging RAW images
Fotoxx
Fotoxx is a free open source Linux program for image editing and collection management
Phototonic
Phototonic – free and open source software for viewing and organizing images with simple editing functions for Linux
digiKam
digiKam – free and open source program for viewing, organizing, and editing photos
KPhotoAlbum
KPhotoAlbum – free and open source software for organizing and viewing images for Linux