fitbitIt started at that stage in a relationship where the exhilaration and newness wears off. After eight months, I could no longer ignore worrisome behaviors. They’d become patterns.

I finally had to confront my Fitbit about its deceptions.

When I was first given my petite Fitbit Zip Wireless Activity Tracker last September, I didn’t just like it. I like-liked it. I’d recently come out of a seven-month relationship with the attractive MyFitnessPal website and smartphone app, an unusually strict disciplinarian (insisting I track all foods and exercise), yet our separation filled me with a wonderful sense of loss. Twenty-five pounds worth.

A stable relationship
Stable relationship wanted

The Fitbit was not supposed to be a rebound relationship, but instead would acknowledge the maturity of my situation and the need for long-term stability. I even professed my like-like after 90 days in a GeekWire column, calling the Zip one of my three favorite tech things of the year.

But Fitbit, those nagging doubts in that post have persisted and grown.

1. You’re into power. When that first battery died after three months instead of the promised four-to-six months, I thought it was an anomaly. That was in early December. I replaced the battery again in February. Then in May.

The official Fitbit Community site showed I was not alone. Since January, there have been dozens of posts in the help forum appropriately titled, “The batteries for my Zip are dying after only two months. Why???” A recent email exchange with Fitbit support to report the issue confirmed that loose Zip contact springs, which hold the battery securely, were not the problem (on some Zips they get jarred out of place). The final, polite support response? “We’ve passed it along to our engineering team.”

Fitbit Zip food
Fitbit Zip food

It’s not just your ravenous appetite for batteries. Often, I’ll receive a low battery warning by email, and minutes later its status changes to medium and then high strength. The false warnings occur multiple times. But when the battery finally dies, it does so without any real warning, taking all its unsynced data with it.

True battery life is 2-3 months, half of the “your Zip battery should last 4-6 months under normal use” statement. At $4-7 per CR2025 battery, you’re an expensive and high-maintenance $60 device.

2. Your accuracy is doubtful. I try not to listen to what others say, but I can’t help notice you may be untrustworthy at times. When I walk with friends who are seeing others like you, allowing for differences in stride and pace, the number of steps registered might vary greatly. Your “Very Active Mins” count for sustained cardio activity often shortchanges me – only yesterday, an intense 35-minute gym workout registered a mere 22 minutes.

The New York Times is paying attention, flatly reporting that “many of these devices are simply inaccurate” based on a writer’s evaluations from The Wirecutter, a technology testing website. Fitness wristbands may be the worst offenders. (At least you’re more like a typical pedometer, better dressed.)

Yet because I can watch you appear to register each and every step I take, I fall prey to the human misconception that just because everything seems to be measured, the measurement is precise.

3. You’re getting a little too popular. I see the covetous looks others give you when I take you out. They want you for their own. Market research firm Canalys confirms it: More than 17 million “wearable bands,” including fitness trackers, are expected to be sold this year. Canalys expects “2014 will be the year that wearables become a key consumer technology.” Plus, consider estimates that 69% of Americans track their weight, diet or exercise, and the market for digital fitness devices is expected to double this year from $330 million last year.

Misled
A misstep, and misled

All of this is almost enough to make me wonder if you’re on the verge of turning into a control freak. Taking my money in exchange for potentially shaky data to which I feel I now have to pay attention, because I’m hooked on it and have paid for it.

But I won’t let that happen. I admit I was angry in March when I tweeted, “If you use data to MAKE decisions for you, you’re doing it wrong. Data should INFORM human decision making.” You – and your MyFitnessPal predecessor – are both, at best, approximations in the service of motivation. Being with you makes me more mindful that keeping my exercise up, calorie intake down and weight stable is a priority that I myself set. Even if you do lie about battery life and make estimates seem like absolutes.

So I’ll keep you around (though I’m sorely tempted by that cute, rechargeable Fitbit One). I’ll give it another try. But let me make one thing clear about the questionable reliability in this relationship.

This time, it’s not me. It’s you.

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