Apps to Retouch photos

GIMP (GNU Image Manipulation Program) is a powerful, free, and open-source raster graphics editor used for image manipulation, retouching, composition, and authoring. It supports a vast array of file formats and provides sophisticated tools comparable to commercial alternatives, making it a versatile choice for photographers, designers, and artists.

GIMPshop was a discontinued modification of the free and open-source GIMP image editor, designed to provide a user interface and workflow closer to Adobe Photoshop for users transitioning between the two programs. It aimed to reduce the learning curve for Photoshop users exploring open-source alternatives.

Photivo is a free and open-source photo processor designed for advanced users. It supports a wide range of RAW and bitmap file formats, offering sophisticated tools for image processing, editing, and conversion.