7/10
Open rating explainerInformationWIREDLong battery life. USB-C charging. Compact size. Multiple easy collar attachments included.TIREDLocation works best if near your phone. Alerts lag when outside of safe zones. Mistakenly alerted that my cat escaped three times during testing. App needs to be open on phone to work properly.As a helicopter pet parent, for many years I attached an Apple AirTag to my cat Basil's collar for extra peace of mind. But with location inaccuracy, no real-time tracking, and dependence on Bluetooth range, this wasn’t an ideal solution. Many pet-tech companies are now developing devices that use cellular coverage to enable real-time location tracking, as well as integrating health-monitoring features into the trackers.
These new smart health collars are sort of like smart rings for people, which let wearers track important metrics like activity, health, and sleep. On the Fi Mini, the connected phone app lets you view daily stats without needing a wearable screen, unlike a smartwatch or fitness tracker.
I tested the Fi Mini smart collar for cats for a month ahead of the launch of my forthcoming guide to smart collars for pets. (I first tested the Tractive Smart Cat Tracker for that guide.) Although my cat stays indoors, I tested the GPS capabilities and the health metrics that an over-invested pet parent like me wants, including sleep and activity tracking to monitor trends over time.
For the Helicopter Pet Parent
Courtesy of FiI tested the Mini designed specifically for cats, which is even smaller, lighter, and more compact than the Mini for dogs. When you purchase, you're actually buying your selected membership plan for GPS tracking and alerting, as well as sleep and activity data, while the device itself comes free.
At the time of writing, a monthly plan is $4.40 per week, billed as $19 per month. But if you prepay for a longer period, you'll save, with 6-month plans billed at $99 twice a year, one-year plans billed at $189 annually, or two-year plans billed at $339 biennially. Plus, Fi runs deep discounts nearly year-round, with offers of $35, $50, and $70 off depending on the plan you choose. And if you have multiple pets with Fis, you can get 5 percent off all membership plans. Each Fi tracker has a 30-day trial and a one-year warranty.
The device itself looks like a small, lightweight black plastic brick, about 1.5 x 1.0 x 0.5 inches. It comes with a strap loop and two types of soft cases, so you have options for attaching the device to your pet's collar. I chose the loop because it's a simple, stretchy rubber material, which made charging much easier because I could just slip it out without needing to remove Basil's entire collar.
The device uses USB-C for charging, which I appreciated, since I have no shortage of those cables around my house, and it took a little over two hours to fully charge. The device claims it can last up to six weeks on a single charge, but I found myself charging it about every two to two and a half weeks. You can add an optional Fi Base in your home to help with location accuracy and extend battery life to six to eight weeks. Instead of using your phone as the point of connection, the Fi Mini connects via Bluetooth to the Fi Base to reduce power consumption and extend battery life.
The Fi Mini Cat Collar's battery life and ease of charging are a vast improvement over the Tractive Smart Cat Tracker, which held a charge for less than five days and required a tricky collar insert and special charger, which made taking off and putting on the device so often quite annoying. Now that I've tested a few of these, simple things like ease of device insertion and infrequent charging make a surprising difference in my excitement to keep using the tracker.
To set up, you'll need to download the connected app, enter Wi-Fi information, and set up your pet's profile by adding birth date, sex, weight, breed, and a photo. Then you'll choose which device you're connecting to the profile, hook it up to the charger, and it will look for the new device using Bluetooth. When I tested, the setup process was immediate.
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Fi Mini App source Molly HigginsOnce you can start tracking, you'll need to map out a safe zone, including “home” and any other spaces where your pet can roam without triggering in-app alerts. This feature would be helpful for someone like my colleague Scott Gilbertson (he's testing a dog-specific tracker on my behalf), who lives on a large swath of land where his dog is free to roam, but he wants to be able to track where his pet goes—and be alerted if they go too far.
But as a person with an indoor-only cat living in a busy part of Brooklyn, the minimum safe zone was already bigger than my apartment, meaning that if Basil escaped and was hiding in a neighbor's yard, I'd not be alerted because he'd still be technically inside the safe zone. This limitation is one of the biggest drawbacks of both the Fi and Tractive trackers.
Within the app, you can add safe zones, more pets with Fi trackers, and other users who can also track and monitor the pet. There's a Health tab where you can add and store things like vet records, receipts, and insurance information, and add vets to easily share your pet's documents and get appointment reminders. You can also set up the Fi app on your Apple Watch to have even quicker access to monitor your pet’s location, activity, and safety (including Lost Mode) without needing a phone.
When you open the app, you'll see a map with live tracking showing where your pet is currently, as well as a notification of the last time they were outside and where they were. With the latter, you can pull up stats like location timeline, showing where they were and when. If you dive into any day when the tracker left the home, it will recreate the route, following the path and calculating the distance the pet traveled.
There's also health-monitoring data from activity and sleep tracking, which is most useful for an indoor-only pet like mine. Like other health-tracking collars, stats for sleep and activity aren't 100 percent accurate, as the app uses GPS to track movement, categorizing “activity” when the animal is moving and “sleep” when the pet is still for a prolonged period. This means that if Basil was awake but stationary, the app may inaccurately categorize this as sleep.
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Fi Mini App source Molly HigginsIn the Rest tab, you can see sleep metrics, including a daily summary of deep sleep, naps, and interruptions during nightly sleep. You can compare this over time, and the app notes how much more or less Basil slept than the night before. It also compares stats historically, by week, month, and year, so you can track trends and better understand your pet's normal sleep schedule.
The Activity tab is similar, tracking activity by day, week, and month, noting in the day's timeline when the pet was most active and for how long. This also compares activity to the day before. I liked looking at the weekly report, comparing days during the week to see which he was most active during and if any patterns in activity popped up.
For example, I noticed that his sleep-versus-activity schedule was similar to mine, except he was active between 4:45 and 6:30 am (while I was still asleep), because that's when his automatic feeder goes off for breakfast and my roommate is getting ready to leave for work. He was most active in the evenings, when I feed him dinner, have dedicated playtime, and my roommates are home, so there's more activity to keep him awake. Historical comparison is also a super helpful way to track whether your pet is sleeping more or becoming more lethargic—an early warning sign of a bigger health problem.
Not Without Its Quirks
Since my cat is indoor-only, I ran some experiments to track location, using GPS on both the Fi Mini tracker and my phone. I also had a friend take the tracker out without my phone nearby to see whether I'd get pinged that “Basil” had left the safe zone.
Although it is better than not being alerted at all, the Fi's GPS has limitations (as did the Tractive tracker I tested). It needs a strong signal to communicate with cell towers for accurate location. If your phone is close to the smart collar (via Bluetooth), it uses that instead of the Fi's GPS, making it more accurate and alerting quicker. If the pet gets loose and is out of range of your phone, it uses the collar's cellular antenna (in this case, Verizon cell towers). But because the Fi's antenna isn't as strong as a phone's, location accuracy is lower, and the connection can be very spotty, especially if your pet is in the country or on acreage where cell towers are farther away.
Therefore, location on the map is more approximate than exact, but it's still more helpful and accurate than something like an AirTag. The Fi Mini also doesn't have heat maps to show frequented areas, and doesn't have true location history, just reports of each route individually.
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Fi Mini App source Molly HigginsWhen I took the tracker outside the safe zone with my phone, Fi alerted me almost immediately that Basil had left and showed his location on the map (using my phone's GPS). So, that worked well, and if he had actually been gone, I'd be able to find him. The few times I had a friend take the tracker without my phone nearby (using the Fi's GPS), the alerts began as soon as it left my home (within a minute) and then as late as 15 minutes after leaving.
The Fi Mini tracker also randomly alerted me that Basil had left the safe zone three times during testing, all while I was away from home. Panicked, I called my roommates each time, and they assured me he was indeed at home, sleeping soundly on the couch. Other users also reported similar problems and said you need to pair with the optional Fi Base accessory to get more precise location tracking and fewer false alerts. This helps to extend battery life and acts as a connection source for the Fi when your pet is at home. I didn't test the optional base addition because it's not needed or included with the Fi Mini cat tracker I tested.
However, I still think for the price, small size, long battery life, and ease of charging, the Fi Mini is worth checking out—especially if you want an alternative to tracking your pet with something like an AirTag. The peace of mind is worth it to me, and I appreciate being able to chart sleep and activity trends over time to better understand Basil's health.
Size42 mm × 30 mm × 12.5 mmWeight16 gramsBatteryUp to six weeksWaterproofIP68Suitable forCats (there's a Mini version for dogs)Compatible collar widthComes with three attachments: strap loop attachment's maximum collar width is 1.25 inches (no minimum); soft case is 0.375 to 1.25 inches; and 3/8-inch soft case requires a collar of 0.375 inchesConnectivityVerizon cellular coverageRangeUnlimited (uses cellular coverage)Location usesGPS and LTECompatible phonesAndroid and iOSBuy at Fi (Cat)Buy at Fi (Dog)$209 $189 at Amazon$189 at Amazon
