Apple Watch Series 12 is a major upgrade to the core health and fitness tracking wearable. That’s because of the new Health Sensing System that includes an even more capable heart rate monitor.

The new hardware doesn’t just extend to more accurate health data. There’s a big change to a small complication that I’m seeing in Apple’s marketing material. It’s just one thing I’m excited about with the new Series 12 and Ultra 4 models.

I really like glancing at my Apple Watch and seeing my recent heart rate. Keeping my resting heart rate low is a good indicator that I’m doing something right with fitness (and managing stress).

For that reason, I often use Apple’s Heart Rate complication on my watch face.

The small, circular version is just a launcher that displays the Heart Rate app icon. The wide version, though, displays a recent heart rate reading, plus a graph of your heart rate since midnight.

I use the wide version since it actually displays information. The app launcher version doesn’t have much utility for me.

Based on Apple’s Apple Watch Series 12 and Ultra 4 marketing material, however, it looks like the smaller heart rate complication is getting a big upgrade.

Apple shows it displaying an actual heart rate for the first time. That means it can be one of the smaller complication sides, not just a three-wide version.

The same complication is still just an app launcher on watchOS 27’s release candidate version on Apple Watch Series 11 and Ultra 3.

The reason is probably because the new Health Sensing System reads heart rate every five seconds, a 60x increase over previous Apple Watch versions.

This means the complication can display a live result. The wide version needs space to provide context for when the heart reading was recorded.

This kind of small change is the sort of thing that adds up and makes for an overall better product that all users can appreciate.

Apple Watch Series 12 is currently available for pre-order from $399. Apple Watch Ultra 4 is available for pre-order from $799. Both models launch in one week on September 18.