Spy Camera Nowadays

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, wristwatch or 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. 

They are often very cheap Mini Electronic Devices with great flexibility. 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 low resolution video onto built-in memory before needing to offload their recorded content.

 

A typical Spy Cam is powered by a rechargeable lithium ion or lithium-ion 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.