We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-09-22 · 6 min read · Independent comparison
If you want a single wearable that also gives you a pair of earbuds you can pop out for calls and music, choose Tuanzi JM03; if you need dedicated in-ear earbuds built for sweaty workouts and light rain, choose Generic S20.
• Tuanzi JM03 — biggest strength: it's a 2-in-1 device: a 1.28-inch round touch smartwatch plus a TWS Bluetooth 5.0 earphone that stores and charges inside it, so you carry one thing instead of two.
• Tuanzi JM03 — biggest trade-off: the earbud itself plays for roughly 2.5 hours per charge, and the earphone is not waterproof even though the watch has life waterproofing.
• Generic S20 — biggest strength: proper in-ear earbuds with Bluetooth 5.1, fingerprint touch controls, adaptive noise cancellation, a waterproof build and a mirror-finish charging case with an LED battery indicator.
• Generic S20 — biggest trade-off: it's earbuds only. There is no screen, no activity tracking, no heart rate or sleep data — just audio.
• Choose Tuanzi JM03 if you want one gadget that tracks your day and hands you a bud for calls on the move.
• Choose Generic S20 if audio and workout durability matter more than any watch functions.
The JM03 is the more unusual product of the two. It's a round 1.28-inch color touchscreen smartwatch on a 22 mm silicone strap, and tucked inside it is a TWS Bluetooth 5.0 earphone. That "one device, two functions" idea is the whole point: the watch is the case, and the bud is the accessory. Bluetooth name is JM03, and it pairs with Android 6.0 and above or iOS 8.0 and above through an app called BrandFit.
On the watch side, the feature list is broad for a budget wearable. You get 24-hour continuous heart rate, sleep tracking, blood pressure readings and a sedentary reminder, plus exercise records covering steps, calories and mileage, and multiple sport modes. There's an alarm clock, information alerts, call reminder and rejection, message push, a multi-language interface, and small conveniences like raise-to-wake, watch face switching, shake-to-take-a-photo and a find-my-phone function. The 350 mAh lithium polymer battery is quoted at 5–15 days of use or more than 30 days of standby when you're not using the earphones.
Who should buy it: people who want step, heart rate and sleep data without wearing two devices, and who want a bud for short calls and music bursts. Who should skip it: anyone who needs all-day earbud playback, gym-proof buds, or serious audio hardware.
Generic S20: Who It's For
The S20 is a straightforward pair of true wireless in-ear earbuds in white, with Bluetooth 5.1 for stable pairing. What stands out in the specs is how the controls work: fingerprint touch sensors handle playback, calls and volume, so there are no buttons to press while you're moving. Noise control is listed as adaptive noise cancellation, and the audio is described as 3D stereo, with a 10-ohm impedance rating.
The build is aimed at activity. It's listed as waterproof, with the stated purpose of protecting against sweat and light rain during intense workouts and outdoor use — a meaningful difference from the JM03's non-waterproof bud. The charging case has a mirror finish and an LED battery indicator, so you can see charge status at a glance instead of guessing. There's no headphone jack, which is normal for this category, and the listed warranty description is 6 months.
The trade-off is what you don't get. There's no screen, no step counting, no heart rate, no sleep data, no reminders. If you want to know how you slept or how far you walked, the S20 tells you nothing. It exists to play audio, take calls and survive a workout.
Who should buy it: runners, gym-goers and commuters who want touch-controlled earbuds that tolerate sweat and rain, plus a case that shows battery level. Who should skip it: anyone who wants health tracking, notifications or a screen on their wrist.
• Best for all-day health tracking → Tuanzi JM03 (24h heart rate, sleep, blood pressure, sedentary reminders).
• Best for workout durability → Generic S20 (waterproof build designed for sweat and light rain; the JM03 earphone is not waterproof).
• Best for long listening sessions → Generic S20. The JM03 earphone is rated at about 2.5 hours per charge.
• Best for carry-one-thing convenience → Tuanzi JM03. The watch holds and charges the earphone, so nothing gets lost in a pocket.
• Best for touch controls and noise handling → Generic S20 (fingerprint touch sensors plus adaptive noise cancellation).
• Best for battery visibility → Generic S20 (LED battery indicator on the mirror-finish case).
• Best for notifications and reminders → Tuanzi JM03 (information alerts, call reminder/rejection, message push, alarm).
• Best for newer Bluetooth → Generic S20 (Bluetooth 5.1 versus the JM03's Bluetooth 5.0).
In my opinion, the right pick comes down to which job you actually need done. If you want one device that tracks your steps, heart rate and sleep and still hands you a bud for calls, I'd buy the Tuanzi JM03 — nothing else in this comparison does both. If your priority is audio that survives sweat and rain with touch controls and a case that shows its charge, I'd buy the Generic S20. I'd lean toward the JM03 for a general everyday user who wants tracking plus occasional listening, and toward the S20 for anyone whose main use is working out. Check the current price on Amazon before deciding, since that's the one thing that can tip a close call.
FAQ
what is tws earbuds
TWS stands for "true wireless stereo" — earbuds with no cable between the two pieces, each connecting independently over Bluetooth. Both products here include TWS audio: the Generic S20 is a standalone TWS earbud set, while the Tuanzi JM03 is a smartwatch with a TWS earphone built into it.
what is tws earbuds means
how much is tws earbuds
That varies enormously by brand, features and build, and it changes over time, so I won't quote a figure. Your best move is to check the current price on Amazon for both the Tuanzi JM03 and the Generic S20 and compare them directly, since the JM03 includes a full smartwatch and the S20 is earbuds only.
how to tws earbuds
Pairing is standard Bluetooth: power the buds on, enable Bluetooth on your phone, and select the device name — "JM03" for the Tuanzi, or the S20's Bluetooth name for the Generic. The JM03 also uses the BrandFit app for its watch features and works with Android 6.0 and above or iOS 8.0 and above.
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See also: tws earbuds, CIRAGO TWS vs Generic TWS AI Real-time, ONES MusPlayE AI vs Generic Earbuds