Besides editing chapters by hand, iFlicks also allows you to add chapters to your video files by importing them from external files. There is no commonly agreed to standard for chapter files, so iFlicks tires to support importing of a wide range of different types.
One of the best sources for chapter information is chapterdb.org. All downloaded chapter information from there can be imported straight into iFlicks.
Among the importable chapter file formats are
.txt and .xml chapters downloaded from chapterdb.org.
.txt chapters exported by mp4chaps.
.chapters files created by ChapterGrabber