Is Fitbit Alta HR The Worlds Slimmest Heart-Rate Tracker?

It's only been six months since the Fitbit Charge 2 was released. It's one of our favorite fitness bands, but Fitbit is back again with a design that could top it. The Fitbit Alta HR, according to Fitbit, is the world's slimmest fitness tracker with continuous heart-rate measurement. It looks much slimmer than the Fitbit Charge 2, that's for sure.

The Alta HR is the same size as the original Alta that was announced last year. It has swappable bands and can track steps, distance, calories burned and sleep. It will also display notifications for incoming calls, text messages and calendar alerts.

The Alta HR will automatically detect various activities like running and biking, but because it lacks a button, you can't manually start a workout like you can on the Charge 2. It also doesn't have the guided breathing sessions that Charge 2 included, and won't track how many floors you climb.

Fitbit says the Alta HR will last up to seven days on a single charge, which is quite the accomplishment given the larger Charge 2 lasts about five days.

The Alta HR will also include a new sleep feature called Sleep Stages that uses the optical heart-rate sensor to estimate how long you spend in light, deep and REM sleep cycles. This feature will also be coming to the Charge 2 and Blaze in the coming weeks.

The Alta HR is available now through preorder for almost the same price as the Charge 2: $149.95. It'll begin shipping in early April. We'll have a full review of the Alta HR in the coming weeks, but from this first impression, this could end up being the best and most practical Fitbit of the bunch. Stay tuned.