Overview

• The staged rollout starts in South Korea with beta testers receiving the update first, with wider regional distribution expected over the coming days.
• The update arrives as firmware L310XXU1BYI4 (BYI4) with the September 1, 2025 security patch, measuring about 160 MB for beta users and roughly 2 GB for others.
• New health features include an Antioxidant Index, Bedtime Guidance for sleep, a Running Coach and Vascular Load analysis.
• Interface changes add a Now Bar for ongoing activities, multi‑widget pages, extended double‑pinch gestures, improved notifications, a personalized app screen and a new charging animation.
• Samsung cites smoother performance with more stable connections, faster responsiveness and optimized sensor processing, and indicates global expansion is imminent with Galaxy Watch 6 beta users next in line.