The OnePlus Watch 4 in black is a smartwatch designed for everyday wear and fitness tracking. It features a stainless steel case with a circular AMOLED display, protected by sapphire crystal glass. The watch offers comprehensive health monitoring, including heart rate tracking, SpO2 measurement, sleep analysis, and stress detection. It supports over 100 workout modes with automatic exercise detection. Built-in GPS provides accurate route tracking without a phone. The device runs on a proprietary operating system optimized for smooth performance and long battery life, with up to 14 days of typical use. Water resistance to 5 ATM allows swimming and showering. The watch comes with a black silicone strap that is comfortable for all-day wear. It is compatible with smartphones running Android 6.0 or later. Key features include notifications for calls and messages, music controls, and a remote camera shutter. The OnePlus Watch 4 is a reliable companion for active lifestyles, offering durability and essential smartwatch functions in a sleek design.