It will be like setting up video conferencing, except for everything.
Your car will go to the wrong place because it failed to account for a leap second, thus breaking gps.
Your fridge will put itself in eco mode because it thinks you're on vacation from misreading your calendar and spoils all your food.
Your front door will forget who you are after you get a haircut and lock you out.
After an automatic system upgrade your shower will no longer produce hot water, because a bug results in the system using Celsius instead of Fahrenheit. Your bug report is ignored for a week and after a dozen people complain you get in an argument with the engineer about whether the place you live in actually exists.
Wait. Who am I kidding... You won't be able to talk to an engineer. All support will be automated and it will be impossible to get the robot to understand your complaint. You'll just have to replace it. I suspect you're going to have to replace things a lot.
On the bright side it will probably be really cheap though.
And then there will be all the outages.
One of these days Uber is going to accidentally send all drivers in a big city to a single location. It'll be the great ai outage of 2018, the first of soon to be monthly occurrences of bizarre system failures we can't begin to imagine.
I feel like someone should write a pg wodehouseesque novel about the "smart" future.