The updates released Tuesday will help resolve some of the problems users have experienced with the Up2, Up3 and Up4, wrote Mimi Huggins, [cq] Jawbone's public relations manager, in an email.
An over-the-air firmware update via either the Android or iOS Up smartphone apps will allow the Up3 and Up4 to collect what Jawbone calls "passive heart rate" data.
Currently, those devices only gather "resting heart rate," which Jawbone defines as the number of times a heart beats when a person is completely at rest, particularly during sleep.
Some critics viewed the Up's ability to measure only rest heart rate as a drawback.
Passive heart rate information, by comparison, will be gathered periodically during the day when a person is still, Jawbone said Tuesday.
How often the devices measure passive heart rate depends on a person's daily activities, Huggins said.
According to Jawbone, capturing both heart readings gives people a more complete view of their health via the Smart Coach feature, which provides people with wellness advice based on the collected data.
The update will also let the Up2, Up3 and Up4 automatically detect when a person falls asleep and wakes up. Previously, users had to tap on the devices twice to switch from day mode to the sleep tracking setting. People's sleeping patterns will automatically appear in the Up app after the tracker syncs with a smartphone.
The software update is being rolled out to customers now, Jawbone said.
Beyond software, the Up2 and Up3 are also getting a style makeover. The Up2 has been redesigned and now has two thin straps instead of a flat strap to secure the tracker to a person's wrist. Some reviewers panned the Up2's clasp, saying it was difficult to secure.
The Up2 will come in six new colors, five of which feature the new strap. Meanwhile, the Up3 is being offered in four new colors.
The prices for the wearables remain the same: the Up2 sells for US$99 and the Up3 for $179. The Up4 is $199.
The Up2 lacks some of the sensors found in the other Up models, preventing the device from tracking a person's heart rate. The Up3 and Up4 have similar functions, but the latter lets people make payments using NFC (near field communication).