Seems like you can basically just control appliances from your smartphone. Seems like such a small benefit (frankly I wouldn't even use it) for such a large effort, not to mention the security and data integrity problems.
Do you care about energy consumption? If you do, you can pull in all that information into a dashboard, evaluate your usage patterns, and craft automations that ensure you're being as efficient as you want. Turn your lights/AC/music on and off when you go from room to room, etc.
Do you care about micro-optimizing your time usage? Create automations that support your daily routine. Tie your coffee maker's smart plug to the next upcoming alarm on your smartphone so you have breakfast ready by the time you get up. Have your garage door open automatically when it's time to go to work, and it's not a holiday, and your phone is at home, and your car is in the garage.
Do you care about eye strain? Have your smart lights change colour to match the light temperature of sunlight throughout the day.
Do you care about silly things that make you feel all powerful? Have your lights turn off, some white noise start, and all the smartphones in the house switch to Do Not Disturb when you plug in your phone to charge next to your bed after 10PM.
The sky is the limit. Over the years I've ping-ponged between "eh, this is not really worth it" and "this is actually incredibly convenient" depending on how my routine has changed.
A smart home is just a problem solver, and everyone has different problems.
The selling features are the boring things. Like connecting a light switch to a lightbulb without having to pull wires through external walls. Or instead of waking up to an annoying alarm clock wake up to your blinds opening.
I had it come on in the morning before I get up, then turn off after I leave for the day. Turn on in the evening, and off at bedtime. You can get mechanical timers for that, but they don't adjust themselves for daylight savings or changing sunrise/sunset times. I was going to set it up to stay on longer when it is dark and overcast out, but I moved to a place with better switch placement, so never did.
For example my thermostat goes up to 85 when I'm not at home, and I set it to a more comfortable temperature before I head home (it'll automatically get more comfortable when I arrive, but on hot days it's nice to pre-cool). You could accomplish something that works maybe 90% as well with lots of effort and a programmable thermostat, but this is more or less automatic.
My entryway light turns on automatically when I get home
I can turn off the lamp upstairs while I'm laying in bed, without having to get up.
Through HomeAssistant (HA) I have a spoken notification to remind me to run the dishwasher right when the electricity time-of-use peak pricing ends each day. It also flashes a light a specific color when it says it so even if the tv is on loud, it'll get my attention.
HA automatically turns on my desk light when my webcam turns on.
HA allows me to remote-start my car with a Siri shortcut, instead of having to dig through the terrible manufactures app.
HA lets me know if I forgot to lock the door to my house.
I also use Alexa to fake lights being turned on throughout the house when I'm away for an extended period of time, so the house doesn't seem as empty. There's a HomeAssistant extension that will record normal behavior in your house, and replay it on demand, which I'm thinking about using to randomize the lights even better.
Some people can figure out how to setup more complex things like "star my coffee when I wake up while gradually bringing the lights up" etc., but the whole experience is abysmal, and worse than Linux in the 90s: you need separate apps (or code stuff with Homebridge), all the devices have extremely limited capabilities (esp. when trying to control them centrally through e.g. Homekit), tgey are extremely brittle and disappear from your network if you look at them funny etc.
It's like Apple's Siri: good in commercials, but only good enough to set a timer. Same here: good in commercials, only good enough to turn on and off based on a simple timer.
Edit: I have a lighting setup with IKEA smart bulbs, Philips Hue lights, a smart plug on the balcony. I doubt I will ever touch another smart device beyond these.
But the few legitimate uses(Door sensors, cameras, checking if you left a heating appliance on, etc) are worth having the system for.
But my house was built in the 70s and has almost 0 ceiling lights in the room. So I started buying smart outlets for the lamps so I could just turn the room off by yelling at it.
My wife switched us to Alexa because she had an app that would let her do her billing through voice (start working on John Doe’s case, stop).
I’ve expanded the lights through the house, I use routines to do stuff like turn off my bedroom light, turn on the fan, and turn on a “rain on a tent” sleep noise thing.
We use it as an intercom for the kids and to make announcements like “dinner time.”
I got an Amazon TV on prime day because it was cheap. It’s kinda handy to be able to yell at the TV when the kids lose the remote. Not super useful.
We all use the things to listen to music. I have mine paired with nice speakers in my office.
I gave up on being spied on. Everything I own is feeding back to Google, Amazon, and Apple. Probably China too with my cheap outlets.
I stick smart devices on a separate 2.4GHz Wi-Fi network that also can’t route to my main one, but that’s just to keep inevitable compromises contained and not fill my network with a bunch of chattering nonsense.
I wish Alexa would let me name it whatever I want vs the choose 1 of 3 names. There are more satisfying names to yell.
(They have not yet attained the self-awareness to set a timer on their phone, and I tire of tracking down the culprit every time I find wet clothes in the washer.)
Setup is Home Assistant Docker image on a Raspberry Pi, MQTT broker, and Tasmota firmware on the smart devices. 95% cloud free except for the push notifications.
Still determining how to solder together a safe dryer temperature sensor module to detect when the dryer is done...
There's no single selling point.
> Seems like you can basically just control appliances from your smartphone.
That might be the case for most consumers, but it's nowhere near the end of what you can do.
One day my 3d printer was working and my robo vacuum bumped into it. I realized that it wasn't a good idea to start a vacuum run if the printer was busy. Both vacuum and printer were already connected to Home Assistant, so the fix was trivial and took a couple of minutes.
I've setup my air filter to turn on whenever the air quality drops - currently watching outside particulate levels, but I'm assembling a device that will allow me to measure inside levels.
We have two portable air conditioners in the same circuit. They can often run together - but not always. They are wired to smart outlets that measure power draw. Automation will turn one of them off if they exceed the recommended power draw - before the breaker gets unhappy. They will also be turned on automatically based on internal temp sensors. So I don't have to worry about my dog.
The important thing is to connect everything that can be connected and start streaming the data. You'll start to find plenty of situations where doing <x> when <y> will be useful. Want to dim the lights when the TV comes on? Easy. Want to turn the coffee maker on and open the blinds when you wake up? Simple. Want to postpone your dryer or washing machine when there's people around? Not a problem. Want a reminder that you forgot the garage door open, or a door open? You can do it.
But what's important to you will depend on your use-case.
We sleep with a sound machine on. I have it set up so when the sound machine goes on, the lights in the bedroom go off and the subwoofer in the living room (adjacent to the bedroom) turns off. We tend to sleep at different times so this allows whoever is still awake to continue watching things without disturbing whoever is sleeping. I also have the outside lights set to turn on at sunset and turn off when the sound machine goes on.
For some reason the lights in my kitchen are controlled by two sets of switches on the opposite side of the room. I added a button to the kitchen island that turns every kitchen light on and off.
Finally, I have the under cabinet lights set to go on at 50% brightness when motion is detected in the kitchen after dark. That way we can grab a drink or a snack without blinding ourselves.
It's all pretty simple stuff but it's nice to have.
Other things include scheduling my lights (internal and external), unlocking my front door and garage with NFC stickers (sticker on my car dashboard or front door).
I like having WRGB light bulbs everywhere that have full control via app/automation. I can wake up with "good morning" mode, have a day mode that's bright white and shifts to amber at sunset. I can go all hunt-for-red-october (pure red) late night. I can hit (or say) "goodnight" and transition the whole house to night mode, etc. Party mode is also rather fun :{
Best of all it works without having to do an expensive PoE retrofit to every switch and bulb in the entire house.
I’m not sure I would have any idea what the best thing is that you could do, however.
After that, it turned into a fun hobby. There's some cool things you can do with it, but it's just a lot of fun to write programs for my house and figure out routines and automations.
All our lights turn on automatically via motion sensors, and stay on based on bluetooth presence detection using our phones and watches. I also have a "night mode" that uses a lower brightness, and switches to using night lights in our hallway and bathrooms.
When we get up in the morning, the coffee machine turns on, the kettle starts boiling, the blinds are opened, and the TV turns on and plays a breakfast news program. (If we get up later then it chooses the TV channel on a 1 hour delay.) I set up a "movie mode" for our living room that turns off all the lights when a movie starts playing on our Roku, and turns on some dim lights when the movie is paused or stopped. We also never need to manually turn off the TV or stereo. When my wife and I both leave the living room and go downstairs, then everything turns off automatically after a few minutes (TV, stereo, any podcasts playing on an Echo, etc.)
When I walk into my office, the lights turn on, my computer wakes up, and it automatically unlocks when I'm wearing my Apple Watch. If I'm away from my office for a few minutes then the screen is locked, the lights turn off, and Spotify is paused. (Then Spotify resumes playing when I come back in, if it was previously paused by an automation.) Whenever my webcam turns on for a Zoom call, my air purifier is switched to quiet mode, and it turns off the fan in the bathroom near my office. It also turns on a ring light for better lighting, and turns it off when the call is finished.
The automations for our alarm system are really useful. Our alarm is automatically armed in "home mode" at night, and "away mode" whenever we are both away from home. It's automatically disarmed in the morning, and when we arrive home.
Our kitchen rangehood extractor fan turns on automatically when we're cooking, or if the pm25 in the kitchen goes above a certain level. Home Assistant also controls all of the heat pumps in our house, and all of our plug-in electric heaters are controlled with a thermostat that uses temp/humidity sensors.
I'm not quite finished yet - I don't have any cameras, and I want to put Amazon Kindle Fire tablets around the house to use as dashboards / controllers. It's also been surprisingly difficult to automatically open the garage door when we arrive home in the car, so I'm planning to use some ESP32s and design a secure protocol using 433 MHz transmitters/receivers. (I wasn't able to get presence detection working reliably with WiFi, even with a long-range antenna.)
Anyway, it's a hobby with lots of fun puzzles and challenges, similar to designing a Rube Goldberg machine or building a model train set. It's nothing life-changing or super important, just something fun to work on.