WatchOS 4, Apple’s latest revision of the software for its smartwatches, will be available to the public on September 19. The operating system, which was first showed off at the company’s Worldwide Developer Conference in June, comes packed with dozens of enhancements aimed at making even the oldest Apple Watch models more useful.

One of the marquee new features is the Siri watch face, which recommends different cards for users to pay attention to depending on context. The Watch will also suggest more personalized workout tips to help users meet fitness goals, and it will connect to certain types of workout equipment.

Apple also gave users a new list view for all of the applications loaded on their Watches. That way, users don’t have to poke their way through the traditional honeycomb grid view in order to find the right app to open, which could prove less than intuitive.

The company is also adding a set of heart health features to the watch. Apple COO Jeff Williams announced a new Apple heart study in partnership with Stanford University researchers, using Watch data to identify heart dysfunctions like arrhythmia. In addition, the Apple Watch will now tell users when their heart rate is spiking while they seem sedentary.

“I believe this kind of capability is what wearables were always intended to do, and that is to detect maladies before they impact people,” said Patrick Moorhead, principal analyst at Moor Insights and Strategy. “This is a great step in the industry.”

While developers had access to beta versions of the new software since WWDC, Apple didn’t make it part of the public beta program. (While it’s simple enough to roll back an iPhone or iPad beta upgrade, doing the same to an Apple Watch requires sending it off for repair.)