Many home security systems offer video doorbells as add-on components, but these devices typically don't work by themselves and require a system hub. However, they usually interact with other system components such as door locks, sirens, and lighting. If you want a standalone smart doorbell that works with other smart devices in your home, look for one that supports IFTTT. This service lets you easily create applets that enable various third-party devices and platforms to interact with each other. Support for Alexa and Google Assistant voice commands is also handy. With these integrations, you can, for example, simply say, "Alexa, show the front door," to launch a live stream on your Echo Show. For more, see our story on how to build your own home security system.