You can charge your cameras or other devices such as a phone while the car is off, but it depends on the type of car charger you are using. If you are using a car charger that is directly plugged into the car’s cigarette lighter or accessory socket, then it may not work when the car is turned off as the socket may only supply power when the car is running. However, if you are using a USB car charger that is plugged into the car’s USB port, then it may work even when the car is turned off, as some cars provide power to the USB ports even when the car is not running.
It’s important to note that even if your car provides power to the USB ports when it’s turned off, it may not be a good idea to leave your hidden camera charging for an extended period of time as it can drain the car’s battery.