Fi Series 3+ Review: Months of Battery, Slower Live Tracking

Most GPS trackers fail the same way: they are dead on the day the dog gets out. A tracker with a three-day battery gets charged on the days you remember. Fi built the Series 3+ around that failure, and the pitch is one number, up to three months per charge. Everything else in this review is the price of that number.

Why the battery is the product

Fi says the collar runs for up to three months, and the maker's own comparison page puts a rival's figure at 42 days at best with power-saving zones, or 20 days without. The method is simple. The collar uses Wi-Fi and Bluetooth when the dog is at home, close to the charging base, and wakes the cellular and GPS radios only after the dog leaves a known safe zone.

Real life is shorter than the claim, and you should plan for it. One independent reviewer reports 4 to 8 weeks for a dog that mostly stays home, 2 to 4 weeks with an hour or two of daily walks, and 1 to 3 days if you leave Lost Dog Mode running. That is still a different category from a tracker you plug in every Sunday.

A collar, not a clip

This is a built-in collar, available for XS to XL dogs, not a tag that goes onto the one you already own. That is both a strength and a restriction. The unit weighs 47 g (1.66 oz) and is 11.5 mm thick on the collar, which Fi's page contrasts with the larger Tractive DOG 6 XL at about 71 g and 20 mm. The rating is IP68 and IP66K, tested in fresh and salt water. Fi quotes 500 lb of pull resistance for the stainless steel frame.

One reviewer lists a minimum dog size of 11.5 lb. Check that against the current sizing guide before ordering for a small dog, because we could only confirm the figure from one secondary source.

If your dog already has a collar with tags and a harness clip you trust, a tracker that clips onto it, such as a Tractive, is simpler. If your dog's collar has been through three seasons of mud, the Fi swap is easier to justify.

Where it loses to Tractive

Live tracking is the weak point. An independent comparison credits Tractive with live updates every two to three seconds. Fi gives no equivalent figure, and users in that comparison report 'last seen 8+ minutes ago' notices while the collar changes networks. Accuracy is typically 5 to 10 meters outdoors per one reviewer, and weaker in dense woods, though the collar keeps working over LTE.

For the usual case, a dog that slipped the gate and is wandering the neighborhood, that is fine: escape alerts fire and the app tracks. For a fast dog on a trail, the slower refresh is the sort of difference you notice at the worst moment.

The three-year bill

Both products need a plan, but the plans are different shapes.

• Fi: membership is mandatory. Fi's comparison page says $189 buys the collar plus the first year. Renewals are quoted at $189 a year by one reviewer, who also lists prepaid $99 per six months and $339 for two years. Another site that tested the earlier Series 3 recorded a $19 monthly option and a $20 activation fee, so check what your checkout shows before you commit.

• Tractive: a cheap device plus a plan. Fi's page quotes $79 plus $120 a year for the DOG 6 XL, and other tests put the standard model near $5 a month.

Over three years, two reviewers estimate Fi at roughly $567 against about $235 to $259 for Tractive. We would treat those as ballpark numbers, since plans and promotions change often, but the gap is real and wide enough to decide the matter for some households.

What the money buys is worth stating fairly: an extended warranty against defects, support by phone, chat and email, unlimited users on one account, multiple dogs per account, and activity, sleep and behavior tracking. Those are real, though few people buy a GPS collar for them.

Who should buy it

Buy it if charging is the reason you stopped using trackers, if your dog swims or rolls in anything, and if a monthly-ish bill is acceptable. It suits a small to medium dog that needs to be worn around the clock.

Skip it if you mostly want the lowest running cost, if you hike with a dog that bolts and need the fastest live view, or if you want to keep your current collar. In those cases Tractive's cheap-device model is the better deal. A GPS tracker also never replaces a fence or a recall command, and Fi does not claim it does.

Verdict

Fi's claim is the right one to make, and the battery mostly backs it up. We rate the Series 3+ at 7.6: the most carefree tracker we know of to wear, held back by a price that doubles over three years and a live view that trails the leader.