A **keychain camera** is an ultra-portable, thumb-sized imaging device designed to blend seamlessly with everyday carry items. These gadgets typically feature a **1/4-inch CMOS sensor**, capable of capturing 1.6-megapixel stills or high-definition 1080p video at 30 frames per second. Designed for spontaneous “lifestyle” photography or discreet security, they often include modern conveniences like **USB-C charging**, microSD card slots for expandable storage up to 128GB, and even small LCD screens for framing shots. Many models, such as the popular Kodak Charmera, double as fashionable “charms” and offer creative features like built-in color filters and digital frames, making them a versatile tool for capturing quick memories or providing a portable layer of personal safety.