Fitness apps: The newest threat to privacy

Then there’s Whistle, which makes round, silver devices that monitor your dog’s activity, linking with users’ fitness trackers to provide activity data and, soon, GPS tracking. Whistle’s offices were resplendent with very well-behaved dogs — all tracked, naturally, by Whistles — and appropriately located near several pet rescue operations off of San Francisco’s Treat Avenue. Whistle co-founder Ben Jacobs was boyish, talkative, eager, and followed everywhere by his dachshund-terrier mix, Duke, who shared many of the same characteristics. Jacobs is bullish on the future of the rapidly expanding market for devices that track what he explained as “the four areas that are valuable, but can’t speak for themselves: our homes, cars, infants, and pets.”

The most prominent company in this first arena is Nest Labs, which sells “smart” thermostats, smoke alarms, and cameras to monitor the home, all of which can be controlled via mobile and will soon communicate with wearables to adjust to fluctuating body temperatures. For the car, Progressive Insurance has been promoting the use of Snapshot, which monitors mileage, time of travel, and how hard you brake, since 2011, luring users with the promise of lower premiums. Nest-owned Dropcam is also vying for a slice of the lucrative pet-monitoring market, which targets the same owners who buy high-end pet food and pet insurance. (Nest, like all of the companies I interviewed for this piece, protects specific sales data.)

And then there are the babies. The most holistic baby-tracking devices come from MimoBaby, whose “Smart Nursery” currently includes a respiration-sensing “baby kimono” that not only protects against SIDS, but combines data about the baby’s feeding, naps, and sleep patterns to determine whether a waking baby needs to be fed or can be settled back to sleep; a smart mobile that zeros in on the sounds and images that put your baby to sleep; and, coming soon, a bottle warmer that will communicate with the kimono to start warming when the baby begins to wake. The ultimate endpoint is an integrated future in which all of these devices work seamlessly with one another — when the baby wakes, for example, your activity monitor decides which parent is less tired and thus should be alerted.