Some, like Netatmo Welcome (€ 200) offer a face recognition function: it can distinguish between family members and intruders. Data is stored on an 8GB SD card included. You can watch a live stream in HD, it can capture every movement thanks to its 130º angle, even at night thanks to its infrared equipment.
Others, like KiWatch 965s (99 €) are provided with an integrated siren, a movement control system (motorized) and go to night view with IR LEDs. The videos here sequences can be saved on the cloud.
The Withings Home (€ 199), whose base is magnetized, analyzes the quality of ambient air and provides a new function with baby cam (pilot and soft music).
Finally, some may be displaced as required. This is the case of the last Logitech, named Logi (€ 199), which embeds a small battery which gives it up to 3 hours of talk time intensive monitoring mode, and up to 12 hours in eco mode . The battery is charged whenever the camera returns to his base.
Please note that some cameras (Kiwatch) require a subscription to access full functionality.