A Spy Camera is a type of micro DVR which is built into a deceptive package and made to resemble a small object, such as a key fob, a wrist watch, or a lipstick case. Known by numerous terms such as cam stick, gum cam, thumb cam, etc., these devices will often function according to their apparent purpose, as in a pen cam that actually writes.
Starting in 2008, spy cams became increasingly popular due to their falling prices. This was a consequence of advances in flash memory technology, which made available cheap, surface-mount chips of over a gigabyte capacity, which meant that the cams could typically record over an hour of video onto built-in memory before needing to offload their recorded content.
A typical spy cam runs off of a rechargeable lithium ion or lithium polymer battery, has small, colored LEDs to indicate its operational status, and is controlled by switches and/or buttons on its surface. It may also have a slot/receptacle for a micro SD flash memory card which will expand its recording capacity by several hours. In order to offload the recorded video, it must be connected to a computer’s USB port, at which point it will function as a conventional thumb drive that contains standard video files.