The Haptic Sense Panel is embedded in the grippy thumb rest and vibrates when pressed, launching Logitech’s Action Ring overlay. This overlay can be customized with various app- and system-level shortcuts. Multiple Action Rings can even be nested if desired, allowing access to highly specific commands. The haptics is a hardware feature that, unsurprisingly, necessitates significant engagement with the company’s software, Logi Options Plus.

The haptics accentuate each interaction with Logitech’s features, including gestures, Action Rings, and Smart Actions (premade or custom macros for task automation). My favorite haptic use, which is initially disabled, allows you to set a small haptic feedback jolt when switching screens, minimizing the “where on earth is my cursor?” moments daily.

Before delving into app integration, it’s essential to note what’s new with the MX Master 4. It features frosted, semi-transparent main buttons that add a touch of elegance. Some might be pleased to learn this model includes a USB-C Bolt transmitter, which other compatible Logitech products (such as the new Signature Slim Solar Plus keyboard) can also connect to.

Regarding battery life, Logitech claims it can last up to 70 days on a full charge (though setting haptics to “high” intensity in the app will result in a shorter charge duration).

Finally, the gesture button has been relocated from the thumb grip—where it was in the MX Master 3S released in 2022—to a dedicated spot next to the other two thumb buttons, just below the horizontal scroll wheel. When held, moving the mouse in a cardinal direction activates the desired action.

Back to the app, Logitech bills the Action Ring as a time-saving feature, an alternative to keyboard shortcuts and moving your cursor across the screen to click something. You don’t have to be a power user to get a lot out of this functionality. For instance, I programmed an Action Ring with a button that auto-launches The Verge, and one that opens WordPress, where we produce articles. There are plugins within Logitech’s app for many third-party apps. Affinity Photo has a version of the Action Ring that appears when I press the Haptic Sense Panel while using the app. It shows some commands that I’m likely to take advantage of, like showing line guides to properly align objects, or simpler stuff like copying and pasting assets.

To be clear, Action Rings aren’t new. The haptic sensations derived from navigating them, on the other hand, are. Clicking the haptics button makes it jolt, as does moving the cursor between the Action Ring’s bubbles. It’s a small, but delightful touch that I appreciate — that is, when I use Action Rings, which I still haven’t trained my brain to rely on when I’m in a flow state at work. I’m sorry to my employer, Vox Media, for all of the time I wasted at work when I could have used Action Rings to enhance my productivity!

With haptics being the main new hardware feature in the MX Master 4, I don’t necessarily think it’s worth upgrading to if you have the MX Master 3S, as it’s similar in many ways. But it’s certainly worth getting instead of the 3S if you’re shopping for a mouse, since the 4 is launching at the same $119.99 price that its predecessor sells for. And, as for those who haven’t used an MX Master-series mouse before, it’s hard to overstate the value of an ergonomically-friendly mouse with a stellar scroll wheel, quiet clicks, and solid battery life. Haptics are just a nice add-on.