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I walked past a display of smart toothbrushes in a shop last year. Not because I was looking for one, but because the packaging made a sufficiently interesting claim that I stopped to read it. The toothbrush connected to an app, tracked brushing pressure, gave you a score after each session, and would apparently tell you which areas you were consistently missing.

My first reaction was the one I suspect most people have: is this a product, or is it a parody of a product? My second reaction, after actually reading the description, was that it addressed a real problem. Brushing too hard damages gum tissue over time. Most people do not know whether they are doing it. The toothbrush measured something genuinely relevant and provided actionable feedback. Whether it was worth the price was a separate question, but it was doing something real.

That experience crystallised something I had been thinking about for a while: the word smart has been applied to so many different things, in such different ways, that it no longer reliably tells you anything useful about whether a device is worth buying or even what it actually does. Understanding what the term actually refers to helps cut through this.

The Word Covers Three Very Different Things

When people call a device smart, they usually mean one or more of the following things. The important point is that these are genuinely different capabilities with different practical implications, and a device can have one without the others.

The first is remote control and connectivity. A device that connects to your home network and can be controlled through an app on your phone is smart in the most basic sense. You can switch it on or off from another room, set a schedule, receive notifications. The device itself is not doing anything particularly intelligent. It is executing instructions that you send to it through a network connection rather than through a physical switch.

This category is useful. A lamp that can be turned off from bed, a plug that cuts power to an iron you left on, a kettle that can be switched on before you get out of bed: these are genuine conveniences. But the device is not making any decisions. It is doing exactly what it is told, just through a different interface.

The second is automation based on rules. A device that can respond to triggers without you manually instructing it each time. A light that turns on when a motion sensor detects movement. A thermostat that adjusts temperature at a scheduled time. A camera that sends a notification when it detects motion. These devices are executing preset rules, if this happens then do that, rather than responding to explicit commands.

This is more useful than pure remote control because it removes the need for ongoing attention. The light in the hallway just comes on when you walk through. The heating just adjusts when you leave the house. The value is in the automation of repetitive decisions rather than in any genuine intelligence.

The third is learning and adaptation. Devices that observe patterns in data over time and adjust their behaviour accordingly without being explicitly programmed to do so. A thermostat that learns when you typically come home and starts heating the house in advance. A camera that learns what a person looks like compared to a passing car and reduces false alerts over time. A music service that learns what you listen to and suggests new things based on that.

This category is the one that most genuinely deserves the word intelligent, though how sophisticated the learning actually is varies enormously between products and is frequently overstated in marketing material.

Why the Distinction Matters When You Are Buying

The reason it is worth understanding these categories is that they help you evaluate whether a specific smart feature is going to change how you actually use something, or whether it is something that sounds impressive in a description and turns out to be irrelevant to your daily life.

Remote control is genuinely useful for devices you frequently want to operate without getting up, that you occasionally need to check on when you are away from home, or that have safety implications if left on accidentally. A smart plug on an iron is an obvious example of the last category. A smart bulb in a bedside lamp is an obvious example of the first.

For devices where none of those scenarios apply, remote control adds cost and a Wi-Fi connection to your network without changing the practical experience of using the device much. The smart toaster is the classic example. Being able to start your toaster from your phone would be useful only if you had a way of placing bread in it while you were not there, which is not how toasters work.

Rule-based automation is useful in proportion to how often the rule triggers and how much it replaces a decision or action you would otherwise have to take manually. A motion sensor that turns on the hallway light saves you from consciously controlling the light every time you walk through. Because hallways are high-traffic areas where the automation fires frequently and consistently, the time and attention saved adds up. A motion sensor that triggers a light in a room you rarely enter saves you from consciously controlling it the few times you walk through, which is less valuable.

Learning-based features are worth evaluating with some scepticism. Manufacturers have strong incentives to describe adaptive behaviour as more sophisticated than it is, because learning sounds more impressive than rules. The practical question is whether the learning actually improves the device's usefulness over time in ways that matter for how you use it. A thermostat that learns your schedule and adjusts heating accordingly is genuinely valuable if your schedule is consistent enough for the learning to be accurate. A device that claims to learn your preferences but in practice just applies a generic average across all its users is not doing anything meaningfully different from one that ships with well-chosen defaults.

The App Is Not the Feature

One of the most common misconceptions about smart devices is treating the presence of an app as evidence of genuine intelligence. Virtually every device sold in the smart home category has an app. The existence of an app tells you nothing useful about what the device can actually do.

Some apps are genuinely useful: they provide data you would not otherwise have, they allow configuration of complex automation rules, they offer useful historical analysis of device behaviour. Some apps are an unnecessary intermediary between you and a device that would be simpler to just operate directly. Some apps are a way to lock you into a subscription or data collection relationship you may not have fully understood when you bought the hardware.

Evaluating the app separately from the hardware is worth doing before buying, particularly for devices where the app functionality is central to the value proposition. User reviews that specifically discuss the app quality over time, rather than just the initial setup experience, are the most useful source of information on this.

What the Word Smart Does Not Mean

Smart does not mean reliable. Some of the most impressive smart home devices are also some of the most frustrating to live with because they require ongoing attention, have poor connectivity, or depend on cloud services that are occasionally unavailable. A device that is slightly less capable but consistently works when you need it is more valuable in daily life than a capable one that requires regular troubleshooting.

Smart does not mean better at its primary function. A smart light bulb that connects to your home network is not necessarily a better light source than a non-smart bulb at the same price point. A smart washing machine that sends you notifications is not necessarily a better washing machine than a non-connected equivalent. The smart features are additions to the primary function, not improvements to it.

Smart does not mean future-proof. The smart home ecosystem has changed significantly enough in recent years that devices bought four or five years ago may no longer be fully functional because manufacturers discontinued their cloud services, stopped updating their apps, or built on protocols that became obsolete. The Matter standard is an attempt to address some of this through cross-platform compatibility, but the risk of a device becoming effectively obsolete through software changes while the hardware is still functional is real and worth factoring into purchasing decisions.

The Useful Question to Ask Before Buying

Rather than asking whether something is smart, the more useful question is: what specific problem does this feature solve, and would it change how I actually use this device?

A smart plug that cuts power to a heater after thirty minutes addresses the specific problem of leaving portable heaters running unsafely. That is a real problem with a clear solution. A smart toilet that remembers your preferred seat temperature addresses a real preference, though how significant that preference is varies by person and climate.

A smart blender that can be controlled from your phone when you are not in the kitchen does not address a problem that most people have, because most people are in the kitchen when they are blending things. The app does not make the blender better at blending. It adds a connection and a subscription requirement to something that worked fine without them.

Applying this question to every smart device claim cuts through most of the marketing language quickly. Useful smart features improve the experience of a device in ways that apply to how you actually use it. Marketing smart features sound impressive in a description and rarely come up in practice.

After several years of building and living with a smart home, the devices I trust are the ones that disappeared into the background immediately because they just worked. The impressive-sounding features I still think about are the ones I no longer use.