An ITHMB file is a data file used by iPhones and photo-capable iPods. It contains a collection of thumbnail images that are stored on the media device. ITHMB files are used for browsing images on iPods or iPhones, as well as for organizing images in photo management programs.
ITHMB files can store up to 25 thumbnail images. Each thumbnail image is linked to a larger image, which is also located on the device. When a user clicks one of the thumbnail images, the larger version of the thumbnail is opened.
NOTE: Since the ITHMB file format is not widely supported, the file can be converted into other, more widely supported image formats using programs such as PicsAid and File Juicer.