Oppo launches the Watch S2 with FatMax fat-burning mode and 10-day battery

Oppo has launched the Watch S2 in China, a CNY 1,599 (approximately $238) smartwatch built around a thin stainless-steel case and a new workout mode that calculates a personal fat-burning heart rate for each wearer. The company unveiled the watch at the launch event for its Find X10 smartphone series, and sales open on September 24.

The Watch S2 has a 1.46-inch AMOLED display rated at 600 nits for everyday use. Brightness rises to 3,000 nits in selected outdoor sports modes so the screen stays legible in direct sunlight. The case measures 8.9mm thick, excluding the sensor bump on the underside, and the watch body weighs 34.5 grams. Buyers can pick from Dynamic Orange, Mist Pink and Mountain Shadow Gray.

Oppo pairs the watch with a segmented fluoroelastomer strap, which the company says is thinner and more breathable than the bands it shipped with earlier models. The overall dimensions remain close to those of the original Oppo Watch S, which debuted in China in October 2025.

FatMax replaces generic heart-rate zones with a single target worked out from the wearer’s height, weight, resting heart rate and VO2 max. During a session, the watch sends real-time prompts to keep the user inside that range and estimates how many grams of fat and carbohydrate they have burned. The Watch S2 supports more than 100 sports modes and uses dual-frequency GPS to record outdoor routes.

Oppo has also reworked the sensor array on the back of the watch. It now combines an eight-channel optical heart-rate sensor, a 16-channel blood-oxygen sensor, an ECG electrode and a temperature sensor. According to Oppo, the optical sensor handles interference 75% better than the previous generation and reaches 98.8% heart-rate accuracy during exercise.

A 60-second health check captures 13 metrics in one reading. The watch also tracks sleep, screens for sleep apnoea and monitors blood-oxygen levels throughout the day.

The Watch S2 runs ColorOS Watch 17, which uses Fluid Cloud to display live updates from services such as transit and food delivery. It can stay connected to two smartphones at the same time and relay notifications from both. The watch also supports NFC transit cards and gesture controls.

Oppo rates battery life at seven days of typical use and up to 10 days with the battery saver enabled. Switching on the always-on display reduces that to about four days. The watch carries a 5ATM water-resistance rating along with IP69 and IP69K certification for dust and water protection.

Oppo also added a Titanium Moon color option to the Watch X3, the flagship smartwatch it introduced in March. The new finish costs CNY 2,799 (approximately $418) and goes on sale the same day.

Oppo has not announced pricing or a release date for the Watch S2 outside China. The original Watch S went on sale in global markets earlier this year at about €259, several months after its Chinese launch.