digiKam is an advanced digital photo management application which makes importing and organizing digital photos a "snap". The photos are organized in albums which can be sorted chronologically, by folder layout or by custom collections.
digiKam vs Capture One opinions
it is a digital photo management application, not a RAW converter
darktable is a virtual lighttable and darkroom for photographers: it manages your digital negatives in a database and lets you view them through a zoomable lighttable. it also enables you to develop raw images and enhance them.
darktable vs Capture One opinions
Darktable is the only RAW editor I use. I have tried Rawtherapee but I think D.T. is better. Besides, there is a long learning curve with both and I am more familiar with D.T.
RawTherapee is a free RAW converter and digital photo processing software. All changes can be applied and batch processed at a convenient time.
Galapix is an image viewer that allows you to directly zoom into large collection of tens of thousand of images from tiny thumbnails down to the images original size fluently with very short load times and no loss of interactivity.This app doesn't have any features at the moment.Discontinued
The project seems to be no longer developed. Last version, 0.2.1, released in April 2014, can be still downloaded from Github.