Luke Angel
An end-of-2021 illustration in warm orange: a dog collar carrying a GPS puck, a small disc-shaped item tracker set apart and crossed out, and a health-signal sparkline rising beside icons for licking, scratching, and sleep — the year location went mainstream and the trackers started reading behavior instead of just steps.

2021 in pet IoT — AirTag landed, Whistle started reading behavior, Halo I won't buy

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#pet-iot#year-in-review#forecast

End of 2021. Eighth year of this. Same ritual: grade last December's bets, log what actually went on a pet, then put next year on the record.

The one-line version: this was the year location went fully mainstream — AirTag put a finder in every Apple household — and the year the collars I already own quietly stopped being step-counters and started being behavior readers. The headline product was the one I didn't end up using. The useful change was the one nobody put on a billboard.

Scoring the 2020 forecast

#PredictionConfidenceOutcomeVerdict
1Apple ships AirTag90%Shipped April 30
2Whistle's health tier reads more than activity75%Whistle Health reads licking/scratching/sleep/eating/drinking
3Petivity (Purina smart litter) announced or ships65%Signals point to a 2022 launch; not at retail yet✓ (partial)
4Litter-Robot 4 announced70%Nothing formal
5Mars Petcare keeps consolidating75%More clinics + pet-tech under the tent
6A GPS-fence competitor with better welfare than a shock collar30%Nothing credible
7An "AirTag on a collar" controversy materializes80%Yes — think-pieces, and Apple stating it outright
8AI behavior-detection for pets reaches a shipping product60%Cameras teasing it; nothing I'd trust yet✗ (close)

Five clean hits, one partial — call it ~69%. The misses are the same two the category keeps failing at: nobody shipped a humane GPS fence (bet 6 — Halo's answer is a shock collar, more below), and the "AI watches your pet" promise (bet 8) is still a demo, not a product. Both are bets I'll make again, because the demand is obvious; it's the execution that isn't here.

A scorecard of eight 2020 predictions for 2021, drawn as a vertical list with a verdict mark per row. Five rows carry a green check: AirTag shipped, Whistle's health tier reads behavior, Mars kept consolidating, and the AirTag-on-collar controversy arrived. One row is a half-filled amber mark: Petivity signalled a 2022 launch but is not at retail. Two rows carry a red cross: no humane GPS-fence competitor to the shock collar, and no trustworthy AI pet-behavior product yet. A note at the foot reads five and a half of eight, with the two misses circled as the category's recurring failures — a humane fence, and AI that actually works.

What actually went on a pet this year

  • An AirTag I tested and took back off. Apple's $29 finder launched in April and within a week half the people I know had one on their keys. I clipped one to Atom's collar for a fortnight to see. The problem is structural, not fixable by me: AirTag is designed to fight unwanted tracking — it chirps when it's away from its owner and pings nearby iPhones that an unknown tag is traveling with them. That's exactly right for stopping a stalker and exactly wrong for a dog, who can't tell me his collar is beeping and whose whole point is that I am intentionally tracking him. Apple says it plainly: AirTag is for objects, not pets. It also has no GPS of its own — it borrows position from whatever iPhone happens to be near, so off the beaten path it goes silent. Useful for my keys. Not a pet tracker. Off it came.
  • Whistle Health on Atom. This is the one that mattered. The Whistle on Atom's collar this year isn't the step-counter the 2013 puck was — Whistle Health watches behavioral signals: how much he licks, how much he scratches, how he sleeps, changes in eating and drinking. Not heart rate, not temperature — nobody consumer-grade does cardiac vitals on a collar yet — but the behavioral layer is a real step past "how many minutes did he move."
  • Fi on Atom, still the daily driver. The non-Mars tracker I switched to keeps earning it. The standout is battery: under normal walk-and-home use it runs weeks between charges, not days — a different universe from the cellular pucks that need a top-up every few days. It only burns down fast in lost-dog mode, querying GPS every minute, which is exactly when you want it to.
  • A second SureFlap door on the back deck (May), reading Joule's and Boson's chips — redundancy for a two-cat household with two exits.

A timeline of the household's pet-tech across 2021, twelve months left to right. April: AirTag enters and is struck through within a fortnight, drawn as a small disc with a beep glyph and a cross. May: a second SureFlap door joins the cat lane. Through the year: Atom's lane runs solid with two bars stacked — Fi for location, Whistle Health for behavior — and a callout marks Whistle Health reading licking, scratching, and sleep rather than just steps. The cat lane shows two SureFlap doors reading Joule and Boson. A note tracks that the most-hyped device of the year, AirTag, is the one that left the house.

What worked

The behavioral baseline is the real upgrade. Six months into Whistle Health and I have a normal band for Atom's licking and scratching — which matters because scratching is one of the earliest tells for skin and allergy trouble, and licking for joint pain or stress. I have no anomaly to report, and that's the point: I'm building the "normal" I'll measure a future abnormal against. That's the whole value of a baseline, and it only exists after you've logged a boring year.

Fi's battery is the quiet win. Weeks between charges means I actually keep it charged, which means it's actually on the dog when it matters. The cellular trackers I've tried fail the human-factors test — a tracker you forget to charge is a dead tracker the day the dog bolts. Fi solved the battery problem the cellular pucks never did.

What didn't

AirTag for pets, as covered — wrong tool by design. I don't fault Apple; the anti-stalking behavior is correct and important. It just means AirTag is a finder for things, and a dog is not a thing that stays put or stays quiet.

Halo Collar — the welfare problem I won't buy past. Halo shipped a GPS "wireless fence" collar with a celebrity trainer's name on it, and the containment mechanism, under the marketing, is a static correction — a shock — when the dog crosses an invisible line. Independent reviews this year confirmed what the spec sheet implies. I keep saying the category needs a humane GPS fence; this isn't it. A shock collar with a GPS chip is still a shock collar. I'll write it up properly, but the verdict is in: not on my dog.

Litter-box per-cat attribution. Still no native multi-cat feature in the gear I own; I'm still leaning on my own CSV export to tell Joule's patterns from Boson's. The hardware can weigh the cat; the software still won't tell me which cat without my help.

Forecast for 2022 — bets, with how sure I am

#What I expect in 2022ConfidenceRead or wish?
1Petivity (Purina) smart-litter monitor reaches retail80%Read — the signals are concrete now
2Litter-Robot 4 is finally announced80%Read — it's overdue
3Mars Petcare makes 3+ more vet-tech / pet-tech acquisitions75%Read — consolidation is the pattern
4We add another dog to the family60%Half wish — it's a family decision, not a market one
5Halo's welfare problem stays a problem (no humane redesign)80%Read, unfortunately
6A non-Mars health tracker reaches market40%Wish — I want the independent option
7The AirTag-on-pets debate grows into real regulatory/press pressure70%Read — the stalking stories aren't going away
8Mars-owned Whistle changes its data-sharing terms55%Read of the risk — watching the opt-outs

The bet I'm rooting for hardest is #4, and it's the least technical one on the list: another dog. If Quark joins us in 2022, the household goes to four animals, and the data-partitioning problem I keep complaining about on the cat side arrives on the dog side too — two dogs, two baselines, two trackers, one app that wants to average them.

A 2022 forecast chart plotting eight predictions as horizontal bars by confidence from zero to one hundred percent, each shaded to mark a grounded read versus a wish. High-confidence reads cluster right: Petivity reaching retail and Litter-Robot 4 announced at eighty percent, Halo's welfare problem persisting at eighty, Mars making more acquisitions at seventy-five. Mid bars: the AirTag-on-pets debate growing at seventy, a Whistle data-terms change at fifty-five. The wishes sit lowest and dashed: adding another dog at sixty marked half-wish, and a non-Mars health tracker at forty. A dividing line separates grounded reads from wishful thinking.

What I'm buying in 2022

  • Petivity smart litter the day it ships — the multi-cat attribution I've wanted for years, if Purina actually solves the "which cat" problem in software.
  • Litter-Robot 4 when it's announced, judged on whether it finally does per-cat natively.
  • A tracker for whatever new dog arrives — and it'll be a Fi, because the battery is the only spec that survives contact with real life.

What's next

Quark, maybe, in 2022 — and if he comes, the next year-in-review is written across four animals instead of three. Two posts I already owe: the Halo Collar teardown (why a GPS shock-fence is the wrong answer to a real problem), and Petivity the moment it's on my floor under a litter box. And the question this notebook has circled since the Mars acquisition keeps tightening: the more of my pets' data lives inside one pet-food conglomerate, the more I want an exit that isn't owned by anyone selling kibble.

Eight years documented. Location went mainstream this year and the trackers learned to read behavior — but the humane fence, the trustworthy AI, and the independent health tracker are all still on the wish side of the table. Same gaps, one more year of waiting on them.

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shares tags: #pet-iot · #year-in-review
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