Why Fitbit Charge 2 is the best fitness wearable money can buy

The new Charge 2 fitness tracker ($150) is the best Fitbit device I've ever tested, and I’ve used every one of the company's products (except for its very first tracker). I'll even take that a step further: Backed by Fitbit's easy-to-use mobile app and opt-in leaderboard, Charge 2 is the best fitness-focused, non-smartwatch wearable you can buy right now.

After a week of using the wristband tracker day and night, I have only three complaints.

The bad stuff about Fitbit Charge 2

1. Charge 2's screen is hard to read in bright sunlight

Outside on a sunny day, Charge 2's OLED screen, like many other Fitbit device screens, becomes hard to read. I've grown to expect this, not only with Fitbits — Surge is the exception because it has a monochrome screen — but with most other wearable displays as well.

The first-gen Apple Watch does the best job of making workout (and other information) easy to read on sunshine-y days, and the Apple Watch Series 2 promises a display that's twice as bright.

2. You can't swim or shower with Fitbit Charge 2

Fitbit finally released a wearable, the upcoming Flex 2, designed for use while swimming or showering. Other wearables, such as Garmin's vivosmart HR+ ($220), have had this "superpower" for some time now. Apple's new Watch Series 2 will track swim workouts as well. So Fitbit's belated dive into the pool comes none too soon.

Despite many things to like about Charge 2, it unfortunately can't go in the pool or shower with you.

3. You can't pause an exercise with Charge 2

Let's say you select "Walk" as an exercise to track and, while you're out, need to stop at the store to buy a couple of items. Unlike with Fitbit's Blaze and Surge fitness watches, you can't pause Charge 2's exercise tracking. It's a minor annoyance, but it's still an annoyance.

The good stuff about Fitbit Charge 2

Charge 2 moves the Fitbit activity-tracking ball forward in several important ways.

1. Cardio Fitness Level and Score

Charge 2 is the first Fitbit device that calculates your "Cardio Fitness Score," a numerical rating that's based on resting heart rate, age, gender, weight, and other data. Charge 2 also tracks your "Cardio Fitness Level," which ranks your fitness score from "Poor" to "Excellent."

Fitbit

It's useful to know how your cardio fitness stacks up to others in your gender and age range. If nothing else, it encourages you to keep up the pace. If you're not satisfied with your score, Charge 2 can help you increase it through more intense exercise. 

2. Charge 2 Interval Workout mode

High-intensity interval training has been shown to increase cardio fitness and health. Fitbit got the memo, and it added its first interval training workout mode to Charge 2. The feature helps make Charge 2 an even better device for athletes, in some respects, than Fitbit's higher-end Blaze or Surge.

With Charge 2, you can determine interval durations and set how frequently you want them to repeat, to seriously up your fitness game. I configured a workout in which I run for three minutes and then walk for three, then repeat, for a total of 30 minutes. Charge 2 vibrates to tell you when to change speed.

Other apps and fitness watches let you create interval training sessions, but it's great to have this capability in a slim, lightweight wearable like Charge 2.

3. Relax mode

Fitbit's "Relax mode" in Charge 2 provides guided breathing sessions of two or five minutes, to help you destress. The feature is easy to initiate, too. You just tap the Charge 2's button to toggle through a few screens, then hold it in to start. (Apple's watchOS 3, which is expected to be released Sept. 13, will feature a new, similar "Breathe" app.)

4. Charge 2 Reminders to Move

Alta was Fitbit's first device with its "Reminders to Move" feature, which vibrates your wrist at 10 minutes to every hour (12:50 p.m. and 1:50 p.m., for example) if you haven't taken at least 250 steps during that hour.

Charge 2 also includes Reminders to Move. And unlike Alta, Charge 2's screen shows how many steps you took during the past hour, so you know how many more you need to "win the hour."

Reminders to Move will also be available for Flex 2 and, soon, Blaze.

Other Charge 2 goodies worth a mention

In my tests, Charge 2's battery lasted between 3.5 and 4.5 days. That's impressive compared to some other Fitbit devices I tested. It also beats the Apple Watch's 18-hour battery. You can expect to charge up Charge 2 about twice a week.

Fitbit's "PurePulse" heart-rate sensor in Charge 2 seems accurate, at least compared to the readings from my Polar chest strap. I did see some brief but noticeable differences between the two heart-rate readings I received during intense cardio workouts. However, the average and maximum beats per minute (bpm) readings for each workout only differed by a few beats between Fitbit's and Polar's readings.

Charge 2 automatically tracks sleep and a variety of exercises. You can choose from several clock faces, too, including my favorite, which shows time, date, the day's total steps, and your current heart rate. Also, like Alta and Blaze, you can easily switch Charge 2's bands. Or you can opt for a "special edition" rose gold or black gunmetal case ($180) each.

Charge 2, like a growing number of Fitbit devices, displays calendar, text-message, and caller-ID alerts from your nearby smartphone. You can't respond to any of these alerts as you can with a smartwatch, however.

A great upgrade to Charge HR

Charge 2 surpasses its predecessor, Charge HR, in every way. Charge 2 also advances Fitbit's activity tracking capabilities and the data it provides users. The device costs $150 — the same price that Charge HR initially cost (it's now $130).

Now that I've spent time with Charge 2, it's hard for me to recommend any other Fitbits, though I have not yet tested Flex 2. For example, Fitbit Blaze lacks some of Charge 2's key features, and it's bigger and bulkier — though it also has a color screen and acts a bit more like a watch. Surge, Fitbit's top-of-the-line tracker, has only one advantage, in my opinion: built-in GPS. 

The bottom line: If you're looking to buy a new Fitbit, do yourself a favor and seriously consider Charge 2.