I have spent genuinely alarming amounts of money on things that promised to make this house smarter and then quietly died or sulked or asked me to disable two-factor authentication. And the single most reliable, most-used piece of automation in the entire place cost about thirty cents and has no brain, no battery, no firmware, and no opinions.

It’s a sticker. An NFC tag. A little paper-thin coil you can buy in a bag of fifty for the price of a coffee, stick to a wall, and tap with your phone to fire off whatever Home Assistant automation you’ve pointed it at.

Thirty cents. Still employed.

That’s the whole magic, and the dumbness is the point. There’s no app on the tag, so there’s nothing to crash. No battery, so nothing to swell into a pillow in your hallway. No region lock, no account, no cloud having a bad day in Virginia. It just sits there being a known location your phone can recognise, and your phone does the thinking.

The trick to NFC tags is knowing which side of the line they fall on, because they’re a genuine gimmick about half the time. A tag by the front door that arms the house and kills the lights as you leave: brilliant, used daily, earns its keep. A tag on the bins to log when you took them out: I did this, I felt very clever for a week, I have not tapped it since, it is a small monument to the gap between what I’ll automate and what I’ll actually do.

The honest rule is this. NFC works where the action is specific, repeated, and tied to a physical place — leaving the house, getting into bed, starting in the gym. It fails where you’re really just trying to feel futuristic. If the automation would be better as a routine you don’t have to think about at all, a tag is a downgrade. If it’s genuinely a "when I’m physically here, do this" moment, the thirty-cent sticker will outlive everything expensive you own.

THE LEDGER

Cost: ~$0.30 each, fifty for the price of a coffee

Actual cost: the dignity of admitting the cheapest thing won

Survives a firmware update? It has no firmware. It will survive me.

Verdict: Buy a bag. Use them for places, not for theatre.