Article updated on September 9, 2021 at 5:00 AM PDT

Fi Series 2 smart collar review: Peace of mind for an active dog and its busy human

Not every feature is essential for a dog owner, but the tracking information could be a lifesaver for any pup.

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Kent German
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Kent German Former senior managing editor / features
Kent was a senior managing editor at CNET News. A veteran of CNET since 2003, he reviewed the first iPhone and worked in both the London and San Francisco offices. When not working, he's planning his next vacation, walking his dog or watching planes land at the airport (yes, really).
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8.0/ 10

Fi Series 2 Smart Collar


  • Location information and push alerts could be incredibly useful during lost-dog emergencies
  • Ability to set multiple safe zones
  • Colorful, waterproof design


  • Base station arrangement can be inconvenient
  • When you're not on Wi-Fi, the app will be a drag on your phone's battery

It was inevitable that the internet of things would eventually make its way into the things we buy for our dogs. It shouldn't be surprising -- we already spoil our best friends with plush beds, bully sticks and winter coats, so it's natural they too should benefit when we make our homes smarter. These connected pet products can range from smart doggie doors and doorbells to a camera that can fling treats to a bored pup, but the Fi Series 2 smart collar is a better starting point for the always-online dog. 

Fi goes a step further than some woof-centric wearables by combining a collar (something every dog person needs) with a smart device. Like its direct competitors, its star selling point is a location-tracking feature that connects to a mobile app. Whether you have an escape-prone puppy or a slower senior dog, knowing when your pooch is on the run, or even on a wander, can be life-saving information for you both. I never put the Fi to that ultimate test during the two weeks that my dog wore it, but I did become engrossed with the location data it delivered. Just note that because the GPS tracking feature uses AT&T's LTE network, you'll need to live in an area with sufficient AT&T service to fully use the collar.

I was less taken with the pedometer and sleep tracker features, filing them under, "nice to know, but not essential." Would I buy one for my own dog? Given the steep premium over standard collar ($79 for the collar plus $99 per year for the tracking service) and the need to keep something else charged, probably not. But for the right owner -- say, a harried human with young kids and an energetic dog that still needs training -- I could see the Fi being a sure bet. 

Not just a strap

If you consider a dog collar to be partly a canine fashion statement, then you'll like the Fi. The basic version comes in four colors -- gray, blue, yellow and a vibrant pink -- each of which has a sharp squiggly line pattern. The aluminum sliding release buckle is rock solid, and there's a convenient loop for attaching your dog's tags. If those designs aren't to your liking, you can choose from more options made by other companies.

Each color comes in four adjustable sizes to fit your dog. The large size was perfect for the 20-inch neck of Shelly, the beagle shepherd we adopted last year. While I can't speak for her (as much as I'd like to), the sturdy woven polyester strap (1-inch wide) felt soft enough to be comfortable. Fi says the collar can take up to 300 pounds of pull resistance, but Shelly is far too calm for me to verify whether that's true. 


My review Fi collar was blue, but it comes in three other colors, each with a wavy design.

Kent German/CNET

I'd just caution against clipping your leash to the Fi. One two occasions when I did so, it slipped off Shelly's neck completely when she suddenly switched directions (there were very important things to sniff). This can happen with collars with a simple buckle design -- fitting them is a delicate balance of being tight enough to remain on and loose enough to not choke. As a leash point I'd recommend using a separate Martingale collar (Fi sells a Martingale band for $29) or better yet, a harness. 

The brains of the Fi are in a small box not much bigger than the buckle. It's made of both plastic and aluminum and has a water-resistance rating of IP86. There's a small light (in seven colors) that you can turn on through the app. Since Shelly doesn't like to walk at night, I didn't use the light to find our way on neighborhood streets after dark (and it's pretty dim anyway). But it was fun to turn it on and watch her amble around the backyard before bed as she found just the right spot to do her business. On the back are the connection points for charging the collar, but they're recessed so they don't run against your dog's neck.


Despite having some brains, the Fi isn't much bigger than a standard dog collar.

Kent German/CNET

Finding your dog

Setting up the Fi starts with creating profiles for your dog and any owners and dog walkers (each designated human must download the app and pair it to your dog's collar). You then set up safe zones, which are areas where your dog spends time and wouldn't need to be tracked. These work by way of a circle on a Google Map that can have a radius as small as 60 feet. 

Your primary safe zone should be your home and yard, which you establish through connecting to Wi-Fi (see below). Through a Bluetooth connection to a phone you can also set safe zones up for a dog park or a doggy daycare. 


Here are three examples of what you'll see on Fi's app: a map of your walks, a history of your dog's location in a day, and your dog's present location with the Lost button at the top right.

Kent German/CNET

You should choose to get push alerts to your phone (they also worked on my Apple Watch) when your dog has left a safe zone (and if applicable, with whom) or when it's left alone outside of a safe zone. During my tests, this feature worked reasonably well with the alert arriving only a couple of minutes after we left home on a walk. It also sent an alert when I left Shelly alone in the car to pick up takeaway. Other times it was a bit too eager, activating when Shelly was at the edge of my home safe zone. But those instances were few.


Safety Zones are set with a circle on Google Maps. 

Kent German/CNET

All of the information your collar delivers is visible through the Fi app (free on both Google Play and the iOS App Store). The lead screen, and the one you're likely to visit most, shows your dog's current location at the top. When Shelly was home, it would say as much. When she was on a walk it would say that, and when we stopped on a walk or she was left alone away from home, it would give the approximate address. If it can't pinpoint an address, it will focus on a nearby landmark.

Clicking on the location will take you to a Google Map showing your dog's approximate location. In my experience it gave an accurate pinpoint as long as I was in an area with adequate LTE reception. Not surprisingly, it got less reliable if reception was poor. The map screen also has the button for activating the Fi's Lost Dog feature. Use this if your pup gets loose -- it will increase the frequency of location pings to the collar, and it will turn on the collar's light. 

Steps and sleep

Below the primary screen is a history of your dog's activity, such as the periods when it was home and when it left home with an owner. This is the information I enjoyed perusing the most -- to see Shelly's activity throughout the day. You'll also get a map of your walks showing the distance traveled, a great feature if you're not already wearing a fitness tracker of your own. Of course, getting all of this information means you'll have to activate location services for the app at all times. 

The tracking was only approximate when I didn't bring my app-enabled phone with me on a walk, which is to be expected. And there was one other quirk: On one occasion the tracking service wasn't able to discern when we ended a walk and then got in the car to drive home. According to the company, this can happen if your dog moves around the car while you're driving. Shelly does love hanging her head out the window.


The fi will track your dog's steps and how many hours it sleeps. I found these stats only mildly interesting.

Kent German/CNET

Like a fitness tracker for humans, the app shows the number of steps your dog takes on a walk. Though I could see this being useful information for a senior dog or a breed that needs lots of exercise, it's not information I needed for a nervous middle-aged rescue who sometimes doesn't like to leave the house. The app gives you a preset goal for your dog's daily steps -- Shelly's was 11,000 steps -- but you can adjust this up or down. If you like you can share the step count with other Fi users to see how your furry friend is ranked against other dogs. I turned this feature off, as I couldn't have cared less.

The Fi also will track your dog's sleep showing in the app when (and for how many hours) it slumbered and when its sleep was interrupted for more than three minutes. It also tracks naps, but that could include any time your dog was awake but laying perfectly still. This was more information I didn't follow, but I imagine others might welcome it.


You need to put the Fi on the base to charge. 

Kent German/CNET

Base and battery life

The Fi comes with a charging base, which, by connecting to your home's Wi-Fi, also serves as the hub of your dog's primary safe zone. That means you'll need to keep the base plugged in at all times for the collar to work best. That wasn't such a bother when at home, but it could be annoying if you're short on electrical outlets around the house. Also, traveling with the base and keeping it plugged in won't always be possible. 

Though the collar can still track your dog's location if you leave the base unplugged (as I did for a couple of days), it will connect to your phone to help pinpoint location instead. That was a huge drain on my phone's battery, giving me less than a day of juice, so be aware.


Since the base also serves as the hub of your dog's primary safe zone, you'll need to keep the base plugged in at all times for the collar to work best.

Kent German/CNET

Promised battery life for the collar depends on how active your dog is. On the high end, it's three months for a dog that doesn't leave the house, though why such a pup would need a Fi is beyond me. If you go for walks while staying on Wi-Fi it's two months, and for active dogs that use both Wi-Fi and LTE/GPS, it's supposed to last for three weeks. Of course, your experience will depend on how often you're off Wi-Fi and the strength of the LTE network where you live.

I walk Shelly for about an hour per day during the week and a bit longer on the weekend. With that schedule I found that the battery lasted closer to two weeks (and as I mentioned, it depleted much faster when I left the charging base unplugged). That's still a respectable amount of time, even if I'm not thrilled at the need to keep another thing charged. 

On the whole, the Fi is an intriguing product for a certain dog owner. I'm not one of them -- my dog is a homebody who doesn't stray far from my side when we're out, and the health data was only mildly interesting. But, if you've ever had a dog get loose, you know how scary that can be. If your pup is prone to exploring on its own, the location information the Fi collar provides could lead to a happy reunion. That kind of insurance may just be worth a dog collar with an annual fee.