Just one day after announcing updates to its Gear smartwatch line, Samsung on Monday revealed the Gear Fit, an activity-tracking wristband that shows the company understands that not every wearable needs to include an exhaustive laundry list of features. See all MWC news. View our MWC live blog.

On its 1.84-inch, curved, 432x128 Super AMOLED screen, the Gear Fit displays a rather modest complement of health data and Galaxy smartphone notifications. Users get basic pedometer data, along with heart rate information, and alerts for incoming calls, SMS, alarms, email, calendar items and even third-party apps. Built-in sensors include an accelerometer, gyroscope and heart-rate sensor.

Now, about that heart rate sensor: Samsung was conspicuously vague about how the sensor works throughout its Samsung Unpacked event at Mobile World Congress in Barcelona. Samsung CEO JK Shin declared it "the first of its kind," but no one in the company's cattle call of executives explained exactly how the sensor collects data. This will be our first line of inquiry as we spend more time with Samsung's wearables during hands-on demos.

Nonetheless, the heart rate sensor keys directly into Samsung's S Health software on Galaxy smartphones. "By tracking your heart rate, the fitness manager will tell you to slow down or speed up if there's a sense you're slacking off," said one Samsung executive on stage.

The Gear Fit is compatible with 20 devices (that's 10 times better device support than what the Galaxy Gear smartwatch offered when it launched about five months ago), and will start shipping on April 11, along with the rest of Samsung's Mobile World Congress line-up. Customers will be able to choose from changeable straps in black, orange and mocha gray. Samsung notes the straps are hypo-allergenic--perhaps a veiled reference to FitBit's Force recall problems.

Battery life is rated for three to four days for typical usage. We'll post more information as it develops.