Losing my dog is one of my biggest fears. If you feel the same, the second-generation Fi Smart Dog Collar can help quell your anxiety. The $129 Fi Series 2 features the same streamlined design that helped earn its predecessor our Editors’ Choice award, along with better performance thanks to improved GPS and LTE antennas for more precise location tracking and faster escape detection, as well as Wi-Fi support to help extend battery life. And in addition to monitoring your dog’s daily activity, the Series 2 tracks its sleep, which can potentially help you identify health issues. It delivered significantly speedier escape alerts in testing than the previous model, giving paranoid pet parents like me greater peace of mind. With these upgrades, the Fi Series 2 remains our Editors’ Choice winner for smart dog collars.
Fi Series 2 Pricing and Design
For $129 ($20 less than the original), you get the Fi Series 2 collar with a tracking unit attached, a charging base, a one-year warranty, and a 30-day GPS/LTE trial. After the free trial, a GPS/LTE subscription costs $99 per year, or you can get a two- or three-year plan for $186 or $248, respectively.
The collar comes in four color options: blue, gray, pink ombre, or yellow, and is interchangeable, so you can easily swap it out for a new one if it gets dirty or your dog grows out of it. Fi offers a range of compatible accessory bands, sold separately.
Meant for dogs weighing 10 pounds or more (so no cats or tiny pups), the collar comes in four sizes: small (for necks measuring 11.5 to 13.5 inches in circumference), medium (13 to 16.5 inches), large (16 to 22.5 inches), and extra large (22 to 34.5 inches). It measures around one inch wide, regardless of which size you choose. To easily figure out your dog’s size, you can lay their existing collar flat and measure it in inches.
For this review, Fi sent me a large yellow collar for my pitbull Bradley, who has an 18.5-inch neck, and it fit perfectly.
In terms of design, not much has changed from the original model. Measuring 1.4 by 2.6 by 0.7 inches (HWD), the actual tracker is about the size of a matchbox and thin enough not to bother my pooch. Unlike some standalone trackers that attach to your dog’s existing collar with velcro strips, the Fi is securely fastened to the collar with metal clips, so you won’t have to worry about it falling off.
It features an armored aluminum faceplate and reinforced internal metal, so it should hold up to scuffles and even bites. Like its predecessor, the Series 2 has an IP68 water/dust rating, which means it’s dust resistant and can withstand complete submersion in up to almost five feet of water for about 30 minutes. Fi says it can also handle salt water spray, so your dog can wear it on a trip to the beach.
The collar can withstand 300 pounds of static pull force, three times that of the original model, making it a better option for strong leash pullers like my dog Bradley. A built-in LED can be turned on for night walks via the Fi app.
Better for Nomadic Dogs
The Series 2 collar has a new GPS antenna, which Fi says offers a 400% improvement in signal sensitivity, for better location tracking in remote areas.
The first-generation model relied on Bluetooth alone—via the Fi charging base, your phone, or another designated owner’s phone—for tracking your dog indoors, where GPS is unreliable. The latest version also supports Wi-Fi (with the ability to connect to up to six networks at a time), so it can track your dog when it’s indoors but out of Bluetooth range, making it a better option for large homes and for those who send their pups to daycare facilities.
These Bluetooth and Wi-Fi connections also help preserve battery life, since GPS/LTE uses a lot of power. As your dog roams around, the collar will dynamically jump from one connection to another to optimize signal strength and save battery.
Like its predecessor, the Series 2 can last up to three months on a charge, but that’s only if your dog stays at home all the time, or with you on walks when you have your phone, and never gets lost. Once the collar is out of Wi-Fi and Bluetooth range (such as when your dog is outside playing in the backyard, or with you on a walk when you don’t have your phone), it uses GPS to acquire a location, and LTE-M, a low-power wide-area cellular network, to send the location to the app.
In Lost Dog mode, which relies on GPS/LTE, the tracker’s battery will last up to two days. “If your dog ever gets out, the Fi Collar will use all network signals to provide the fastest and most reliable notification of their escape,” the company says.
My dog spends a lot of time outside hunting lizards and sunbathing in the backyard, and I often take him on walks around my neighborhood without my phone. Under these circumstances, we managed to drain the Series 2’s battery in just 10 days, though a Fi spokesperson said this was due to a Wi-Fi connection bug that has now been fixed. Since then, the tracker has been draining about 5% per day, which would give us around 20 days of juice. In comparison, when we tested the Series 1 with a more sedentary, indoor dog, the collar still had 18% battery life after one month of use. Under those circumstances, we’d expect similar if not better results from the Series 2.
Setting Up the Fi Collar
To set up the Fi, just download the app (available for Android and iOS), accept the Bluetooth pairing request, and create an account if you don’t already have one.
Next, the app will ask you to create a profile for your pooch, including their name, gender, whether they are purebred or mixed, their breed (or dominant breed if they’re a mutt), birthday (or adoption date), and weight. Fi gives you the option to add a photo of your dog from your phone’s camera, gallery, or Instagram. If you link an Instagram account, the handle will be visible to other Fi users. Bradley has his own Instagram, so I linked it to his Fi profile.
My one small gripe about the profile-creation process is that the app doesn’t differentiate between birthday and adoption date, though it says to input the latter if you don’t know the former. I don’t know Bradley’s actual birthday because he was a stray, but I adopted him on September 24, 2019, so I entered that date when setting up his account. Now on his profile, it says Bradley is one year old, because the app is using his adoption date as his birthday. In reality, according to his vet, he was around 1.5 years old when I adopted him, which makes him about 3.5 years old now. To fix the age on his profile, I’d have to make up a birthday around when I think he might have been born. I wish there was an option to just specify your dog’s approximate age, which would be a lot easier.
The Fi comes with a small charging base, which the company says to set up near where your dog spends most of its time. As mentioned, the Fi base helps extend the collar’s battery life, but it needs to be plugged in all the time. Once the base is activated, you’ll see a green check mark in the app. It then walks you through the Wi-Fi setup process so you can connect the charging base to your home network.
Next, the app asks for permission to use your phone’s location data, and has you create a Safe Zone where your dog is allowed to roam freely. The Safe Zone is depicted on an integrated Google Map as a blue circle (the only shape currently available). You can pinch-zoom in or out to increase or decrease the Zone’s area, though it must have a minimum radius of 60 feet. The goal of the Safe Zone is for Fi to notify you as soon as your dog exits the area without you.
The app also asks to use your phone’s motion and fitness activity data (which it says improves walk-tracking accuracy), to send you push notifications (to alert you if your dog escapes or when the tracker is running low on battery), and to access your contacts (so you can easily find friends on the Fi platform). During the setup process, you’re given the option to invite a co-owner or dog walker, so they can help keep an eye on your furbaby. Those added as an owner have full access to your dog’s location and the ability to invite other owners or walkers.
Finally, to activate the collar, you simply place it on the charging base. When successfully activated, you’ll see a check mark in the app.
An Activity Tracker and Social Network for Dogs
The Fi app has five tabs on the bottom: Live, Discover, Rank, Activity/Sleep, and Profile.
In the Live tab, you’ll see a card at the top showing your dog’s current location, along with the tracker’s battery level. To view the location on a map, just tap the Live card. Below the Live card is a timeline of their activity. For each walk, it shows the time, duration, distance, a map of the route, and step count. For a recent 0.4-mile walk around the neighborhood, for instance, it said Bradley took 3,136 steps.
The Discover tab is basically Instagram for dogs. Here, you can scroll through a feed of dog photos uploaded by other Fi users, like and comment on your favorites, and add your own. You can click on a dog’s profile to see all their photos and follow them. To add your own, tap the camera icon in the top right corner, select a photo from your library or snap a new one, add a filter and caption, and press Share. If you have your pet’s Instagram account linked with the Fi app, you’ll have the option to automatically upload the photo there as well.
In Rank, it shows how your pooch stacks up against other Fi dogs, based on the past 28 days of activity. There are leaderboards for overall rank, breed rank, your state, and your city. With around 290,000 steps at the time of this writing, Bradley ranks within the top 49% of Fi dogs overall, but is nowhere near the top of the pack: The current number one Fi dog, a Pembroke Welsh Corgi named Kuz Kuz, has more than four million steps! The app shows that Bradley ranks among the top 41% among American Pit Bull Terriers and the top 42% of all dogs in Florida. Locally, he ranks number two, but only has about half the number of steps as our area’s current leaderboard champion, a German Shorthaired Pointer named Herschel.
In the Activity/Sleep tab, it shows your dog’s progress toward its daily activity goal at the top, including its current step count and distance traveled that day. The app automatically sets a step goal for your pup (Bradley’s is 13,500 steps per day, 94,500 per week, or 418,500 per month). If you find the step goal too easy or ambitious, you can manually edit it as desired. Here you can also toggle graphs showing your dog’s activity per hour, day, week, and month. If you have notifications enabled, the app will send you one when your pup has reached its daily step goal. It also keeps a record of your dog’s longest streak meeting their daily activity goal; Bradley’s is five days so far.
In addition to monitoring your dog’s activity, the Fi Series 2 will track its sleep. When you open the Sleep section of the Activity/Sleep tab, it shows graphs of your dog’s shut eye the previous night, including their total time asleep and the number of interruptions. Here you can also view hourly, daily, weekly, and monthly graphs of their sleep. The graphs even differentiate sleep at night and naps during the day. Over the past month, for instance, it says Bradley has averaged 11.2 hours of sleep per night and 7.2 hours of nap time per day, for a total of 18.4 hours of rest each day.
A sudden decrease in your pet’s activity level, or an increase in sleep interruptions, can be a red flag that something’s amiss. “Sleep is incredibly important for dogs and an early indicator of issues, such as if your dog is getting up throughout the night to drink more,” Fi veterinary consultant Dr. Jeff Werber said in a statement.
Finally, in the Profile tab, you can view and edit your pup’s public Fi profile and access other settings. From the menu in the upper right corner of this tab, you can edit and add Safe Zones, Wi-Fi networks, and charging bases, as well as invite other owners and dog walkers, adjust your alert settings, run a diagnostic test to ensure your collar is working correctly, and access Fi’s useful Help Center. In testing, I found the Fi system very user-friendly and reliable, though you should be prepared to spend some time browsing the Help Center and familiarizing yourself with its features to get the most out of the product.
Finding a Lost Pet
If your dog exits a designated Safe Zone without you, the Fi app will send you a push notification. In the Alert Settings menu, you can opt to get notifications via both push and text, or turn them off entirely. In testing, the Series 2 typically took around two to three minutes to send me an escape alert after Bradley exited the Safe Zone. This represents a significant improvement in response times compared with the original, which took at least 3.5 minutes in testing.
If your dog goes missing, you can activate Lost Dog Mode in a few taps (tap the Live card, then select the red Lost button in the top right corner). In Lost Dog Mode, the collar will attempt to locate it once per minute using GPS/LTE, and the LED on the tracker will pulse red to make your dog easier to spot at night (though you can turn off the light if the battery starts getting low). The app will also provide directions to help you find your pooch. Fi says to test Lost Dog mode so you’re familiar with how the feature works if you ever need to use it.
The Smartest Dog Collar
The Series 2 Fi Smart Dog Collar features a new GPS antenna for superior location tracking in remote areas, an improved LTE antenna for faster escape alerts, reinforced hardware for strong leash pullers, and a new sleep-tracking feature. It also adds Wi-Fi support, which helps save battery life when your dog is outside the limited Bluetooth range of your phone or the Fi charging base, making it a better option for dogs who travel often and/or live in large houses. And while it still requires a subscription for GPS/LTE functionality, it costs $20 less than the original upfront. All of these features—and especially the fact that it delivered the fastest escape alerts in testing—makes the Fi Series 2 our new Editors’ Choice winner.
