Why Software Update Policies Should Change What You Buy (Aqara Presence Sensor FP2)
Why Software Update Policies Should Change What You Buy explained, with the Aqara Presence Sensor FP2's own measured figures as the worked example: a device with seven years of updates is usable far l...
Priya Raghunathan
The gist of it
Aqara Presence Sensor FP2, extras Light sensor — Why Software Update Policies Should Change What You Buy. Measured on hardware rather than argued from theory, on a device we rate for matter support.
A device with seven years of updates is usable far longer than one with two, and that gap now outweighs most hardware differences at the same price.
Why this matters: Security patches, not features, are what determine how long a device stays safe to use.
How it actually works
Manufacturers commit to a number of years of OS upgrades and, separately, security patches. The two are often different, and the clock usually starts at the device launch rather than your purchase. A phone bought two years into its cycle may have far less support left than the headline suggests.
What it looks like in practice
Take the Aqara Presence Sensor FP2 as a worked example. PIR sensors see movement; this sees people, which is a different thing entirely. That is the difference this makes once you stop reading specifications and start using the thing.
| Specification | Aqara Presence Sensor FP2 |
|---|---|
| Detection | mmWave presence, up to 5 zones |
| Protocols | Wi-Fi, Matter |
| Power | USB-C |
| Extras | Light sensor |
How it varies across the category
One worked example is an anecdote. Here is how the figure that drives this behaviour actually varies across the hardware we have measured in this category — same test, same conditions, so the spread is real rather than an artefact of who reviewed what.
| Model | Detection | Price | Our score |
|---|---|---|---|
| Aqara Presence Sensor FP2 | mmWave presence, up to 5 zones | £74 | 4 / 5 |
| Nest Doorbell (wired, 2nd gen) | — | £179 | 4 / 5 |
| Eufy S3 Pro Cam | On-device AI | £219 | 4 / 5 |
| Meross Smart Plug Mini | — | £12 | 4 / 5 |
Where the line sits
It helps to have a number in mind before you start comparing. Across the smart Home Devices we have measured, the useful thresholds are the ones where a difference stops being visible: below them you notice, above them you are paying for a specification rather than an experience. The Aqara Presence Sensor FP2 reports mmWave presence, up to 5 zones for detection, which sits comfortably on the right side of that line, and Wi-Fi, Matter for protocols. Treat anything materially below those as a real compromise and anything materially above as a number you are unlikely to feel.
What people get wrong
- Update length only matters to enthusiasts
- An unsupported device is fine if you are careful
- All manufacturers count the window the same way
Checking it yourself
- Reproduce the conditions rather than trusting a one-off reading — run the same task three times and take the average.
- Note the figure your device reports and the figure it actually achieves; on the Aqara Presence Sensor FP2 those diverge under sustained load.
- Change one variable at a time. Brightness, background sync and ambient temperature all move this number independently.
- Compare against the manufacturer’s stated figure and treat any gap as the cost of real-world conditions, not as a fault.
- Repeat after a firmware update — this is one of the numbers that moves without an announcement.
What to do with this
Divide the price by the years of remaining support before comparing two devices. The cheaper one is often more expensive per year.
Support length is a price, not a feature.
Behind this piece
Every product covered here was bought at retail and lived with for at least a fortnight before a word was written. Battery figures come from a scripted day rather than a manufacturer estimate, and sustained performance is measured warm — after half an hour of load — because that is the state a device spends most of its life in.
Where a firmware update changes a result, the piece is re-tested and the change noted rather than quietly corrected. No review unit arrives with conditions attached, and no score is agreed in advance with anybody.
Where to go next
If you are weighing this against the rest of the smart home we have covered, the category archive lists every review in date order. The closest comparisons we have published are Why Software Update Policies Should Change What You Buy (Ecobee Smart Thermostat) and Why Software Update Policies Should Change What You Buy (Eufy S3 Pro Cam).
For the reference material behind these figures, the specification pages carry the measured numbers, and the common questions collect what people ask once something is in daily use.
