ConsFirst / Pet GPS trackers / Compare
Fi Series 3+ Smart Dog Collar vs Apple AirTag (2nd Generation)
Which one has the downsides you can live with?
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The short answer
Fi Series 3+ Smart Dog Collar ranks higher (#1 vs #2 of 7) and scores better on location accuracy, app & alerts, fit & durability. Apple AirTag (2nd Generation) wins on battery life, ongoing cost.
The biggest complaint about the Fi Series 3+ Smart Dog Collar is needs its own collar, which can rattle; for the Apple AirTag (2nd Generation) it's no real-time tracking. Pick the one whose catch bothers you less.
Side by side
| Fi Series 3+ Smart Dog Collar | Apple AirTag (2nd Generation) | |
|---|---|---|
| Rank in pet gps trackers | #1 | #2 |
| Price tier | $$ | $ |
| Type | GPS + cellular | Bluetooth tag |
| Amazon 1–2★ share | 15% | 8% |
| Overall score | 3.9 | 3.5 |
| Location accuracy | 4.0 | 2.0 |
| Battery life | 4.5 | 5.0 |
| App & alerts | 3.5 | 2.5 |
| Ongoing cost | 3.0 | 5.0 |
| Fit & durability | 4.5 | 3.0 |
Price tiers: $ under $50 · $$ $50–200 · $$$ over $200 (device only, before the plan). Highlighted = clearly better (a score gap of 0.3 or more, or a 1–2★ share at least 3 points lower). Scores are explained, with sources, on each product's page.
Top complaints
Fi Series 3+ Smart Dog Collar
- Needs its own collar, which can rattle
It attaches only to collars with Fi's proprietary endlinks. Wirecutter says some users, including one long-term tester, complain about the metal endlinks clicking or rattling.
Source: Wirecutter (GPS pet trackers) - Goes offline; zigzag paths
Wirecutter saw the tracker go offline or fail to connect more often than Tractive's, and its live path sometimes zigzagged through buildings. It also works better if the app stays open in the background.
Source: Wirecutter (GPS pet trackers) - Mixed accuracy and battery for owners
Amazon's review summary says accuracy and durability are mixed, and some owners need to charge every 5 to 6 days while others report phenomenal battery life. Some find it too expensive for what it does.
Apple AirTag (2nd Generation)
- No real-time tracking
Wirecutter's AirTag test updated the dog's location far less often than any GPS tracker, only when the dog came within Bluetooth range of an iPhone, and sometimes not at all. PCMag says the location is only as accurate as the last iPhone that passed by.
- Not designed for pets
PCMag notes Apple clearly states the AirTag is meant to find lost items, not keep tabs on family, friends or pets. Wirecutter dismissed general-purpose Bluetooth trackers for finding a pet on the run.
- iPhone only; needs a holder
PCMag lists no Android support and no way to attach it without accessories. Amazon owners report mixed connectivity, with some saying it won't pair with their iPhone.
Who should pick which
Pick the Fi Series 3+ Smart Dog Collar if
A slim, tough tracker for active or swimming dogs
Small dogs (Fi's size chart starts at 5 lb)
Activity and behavior insights
Skip it if: You want to keep your dog's current collar; You won't leave the Fi app running in the background; You live where cell coverage is patchy
Pick the Apple AirTag (2nd Generation) if
Indoor cats or dogs that hide nearby
iPhone owners on a tight budget
A backup to a GPS tracker
Skip it if: Your dog runs off in rural or low-traffic areas; You use Android; You need escape alerts or live tracking
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