applewatch se3, which lasts longer speaker or airpods ??

According to Apple, the Apple Watch SE 3 has an All-day battery life, up to 18 hours of normal use and up to 32 hours in Low Power Mode. So it should not matter if you are using your speaker or AirPods, if both devices have been charged before the workout.

I prefer to use my AirPods Pro 2, if I feel like listening to music during my indoor workout. Outside I'd rather listen to the ambient noise 🙂

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6 . All-day battery life is based on the following use: 300 time checks, 90 notifications, 15 minutes of app use, and a 60-minute workout with music playback from Apple Watch via Bluetooth, over the course of 18 hours; Apple Watch SE 3 (GPS) usage includes connection to iPhone via Bluetooth during the entire 18-hour test; Apple Watch SE 3 (GPS + Cellular) usage includes a total of 4 hours of cellular connection and 14 hours of connection to iPhone via Bluetooth over the course of 18 hours. Battery life in Low Power Mode including sleep tracking is based on the following use: 430 time checks, 130 notifications, 20 minutes of app use, a 60-minute workout with music playback from Apple Watch via Bluetooth, and 6 hours of sleep tracking over the course of 32 hours; Apple Watch SE 3 (GPS) usage includes connection to iPhone via Bluetooth during the entire 32-hour test; Apple Watch SE 3 (GPS + Cellular) usage includes on-demand cellular connection and 24 hours of connection to iPhone via Bluetooth over the course of 32 hours. Testing conducted by Apple in July and August 2025 using preproduction Apple Watch SE 3 (GPS) and Apple Watch SE 3 (GPS + Cellular), each paired with an iPhone; all devices tested with prerelease software. Battery life varies by use, configuration, cellular network, signal strength, and many other factors; actual results will vary.

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copied from: Apple Watch SE 3 - Technical Specifications - Apple