Endel is an adaptive-audio app that generates personalized soundscapes for focus, relaxation, sleep, and on-the-go listening. The generative engine reacts to inputs like time of day, weather, heart rate (via Apple Health) and circadian rhythm, producing a continuous stream rather than fixed tracks. The team has published research collaborations and pieces with neuroscientists, and Endel even released an algorithm-driven album with Warner Music.

The product runs on iOS, Android, macOS, watchOS, Apple TV, Amazon Alexa, and the web, with a subscription model and a free trial. It has been featured in publications like WIRED and The Verge, and is one of the better-known examples of generative ambient audio with a real research-backed story rather than a generic relaxation app.