Smart home
The phrase smart home refers to home automation devices that have internet access. Home automation, a broader category, includes any device that can be monitored or controlled via wireless radio signals, not just those having internet access. Smart home devices have become common for voice recognition, lighting, keyless door entry, security cameras, sensors (for temperature, motion, water, etc.), on/off switches, thermostats, TV's and streaming devices, smoke detectors, robotic vacuum cleaners, lawn watering systems, and many more. Whether the device is powered by the electrical grid or by battery, if it uses the home Wi-Fi network and if an internet logon needs to be created to use it, then it is smart home technology.
Collectively, all the smart home devices on every home's Wi-Fi network helps to make up what is called the Internet of Things (IoT), a huge sea of sensors and control devices across the world that are capable of being accessed from afar via the internet (and thus, potentially, available for spying or hacking). Today, homes may contain dozens or even hundreds of such devices, and consumers may enjoy their benefits while knowing little about how they work, or even realizing that they are present.
Not all home automation is "smart"
Many remotely controllable devices do not require internet access. They may instead have physical control devices that use either RF (“Radio Frequency”) or IR (“Infrared”) beams, two different kinds of energy used in remote controls to communicate commands. Examples are a wireless doorbell, a battery-operated wildlife camera with Bluetooth file transfer to a computer, a programmable thermostat that is programmed on the device itself, garage door openers, and keyless car entry. Non-"smart" home automation may still have very serious security risks associated with it, because the control signals can be hijacked by bad actors with the right signaling equipment. Garage door openers are of particular note in this regard. Modern automobiles, in fact, are full of automation similar to home automation, and cars are hackable by bad actors in a number of ways. See Wikipedia's Automotive hacking article for more information.
A jungle of incompatible and competing products
At present, consumers must make sure that the smart device they wish to use is specified to be compatible whichever phone/tablet operating system they use (Apple vs. Android). Since smart home products emerged in the absence of any standard, a morass of competing methods for networking, control and monitoring now exist. Consumers may need to buy an expensive hub, or bridge, device that is specific to one vendor. Products made by different manufacturers but performing the same function are typically not interoperable. Consumers often need to open a different app on their smartphone or tablet in order to control devices by each manufacturer. This may make it too expensive and awkward to try out competing devices, leaving consumers stuck with the product they bought originally or else having to add yet more apps to their phones.
Serious security concerns
Security for smart home products has been uneven and sometimes seriously inadequate. Smart thermostats which can monitor whether a home's occupants are present or not, entry-way locks, and other smart home devices can present very real dangers if hackers can access them.
Matter, emerging standard as of 2023: Secure, reliable, and interoperable
About ten years ago, industry consortiums formed to work on standards for smart home device communications, and their underlying wireless communications, which would make it possible for products from all vendors to work together seamlessly and provide fast performance, privacy, and security and would work even if there is not connection to the outside internet (i.e., no connection to "the cloud" or to servers). This resulted in a new standard, called Matter whose first version was finalized in Sept. 2022 and emerging in the marketplace during 2023. Most major vendors have committed to adhering to the basics of the emerging standard within a few years. Another important, emerging standard for smart home devices is Thread, which specifies how the wireless communications among smart home devices will work when using the Matter standard.
Smart home product examples
Philips Hue lights
Nest Learning Thermostat + remote room sensors
The Nest Learning Thermostat is a smart home device from Google with extraordinary capabilities. It's elegant physical user interface is styled after the old round thermostats in ubiquitous use since the 1950's, but every one of its complex functions can be reached through this physical interface should the internet not be available. Nest has been a subsidiary of Google since 2014, and Google required all Nest users to set up two-factor authentication using their Google accounts, so the product is relatively secure. And that's a relief, because the Nest can tell whether the room it's in is occupied or not. To be more precise, it detects when someone moves in front of it (reaching out several feet). It also detects humidity and the outside temperature, and based on many parameters which the user can set, it is capable of truly intricate behavior, including programming itself to a schedule by observing how the household occupants choose to adjust the thermostat explicitly over a few weeks. This model can also have remote sensors (which must be bought separately) for different rooms so that, at any time, the temperature can be adjusted according to whichever room one wishes. The sensor also shows the humidity in that room and how it compares with other rooms.
The Nest Learning Thermostat's most amazing advance feature is probably being able to detect, by means of the location of the smartphone of occupants, whether anyone is at home, and thus (if wished) adjusting temperatures while away and then, once any occupant heads to the home, having the temperatures restore to normal by the time one arrives.
It can be truly challenging to figure out how to use all those advanced settings, and the Nest is reknowned for creating uncomfortable, annoying temperatures during its "learning" phase. But the Nest can also be used by ignoring and not using most of the "fancy" features. It is drop-dead easy, in the app, to create a daily schedule for the thermostat and duplicate it across every day of the week. It is easy to have the house air handler stir the air for a few minutes per hour on a schedule, or not. It is easy to query and control the basic thermostat temperature setting via smart speakers such as a Google Hub or Amazon Alexa.