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.

In 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.