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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want a straightforward pair of true-wireless earbuds for music, calls and workouts, choose Lenovo LP40; if you need one wearable that puts a smartwatch on your wrist and earbuds in your ears, choose ZJX Watch. These two products get compared a lot because both are affordable Bluetooth audio gadgets — but they solve completely different problems. One is audio-only; the other is a 2-in-1 watch-plus-earbuds combo. In my opinion, picking between them is less about which is "better" and more about which job you actually need done.
• Lenovo LP40 — biggest strength: dedicated true-wireless earbuds with Bluetooth 5.1, dual-ear use (one or both buds), touch controls and intelligent noise reduction for calls, with up to 5 hours of music per charge.
• Lenovo LP40 — biggest trade-off: it's audio only. No screen, no fitness tracking, no notifications on your wrist — if you want a watch, this isn't one.
• ZJX Watch — biggest strength: a 2-in-1 device that combines a 1.52-inch full-touch HD smartwatch with integrated TWS earbuds, plus fitness tracking (steps, distance, calories, heart rate) and message reminders.
• ZJX Watch — biggest trade-off: it's a hybrid. The audio and the watch are built around each other, so you get convenience and features rather than a pure, dedicated listening experience.
• Who each pick is for: Lenovo LP40 for anyone who mainly wants reliable everyday earbuds; ZJX Watch for anyone who wants wrist notifications and fitness tracking and doesn't want to carry two separate gadgets.
The Lenovo LP40 is built for one thing and does it without distractions: wireless listening. It runs Bluetooth 5.1, which the data sheet lists as a fast, stable, low-power connection compatible with most phones, tablets and laptops. The dual-ear design means you can use one earbud or both — handy for keeping one ear open while cycling or walking, or for stretching a single bud's battery. The built-in composite metal dynamic coil driver (13 mm, 20Hz–20KHz, with AAC/SBC decoding) handles the audio, and each earbud carries a microphone, so calls work in stereo mode too.
Who should buy it? Anyone whose priority is music and calls — commuters, gym-goers, students, people who take a lot of voice calls and want a mic on both sides. Who should skip it? If you want a screen on your wrist, health tracking, or notifications you can glance at without pulling out your phone, the LP40 can't do any of that. It's an audio product, full stop. If that's all you need, that's not a weakness — it's focus.
ZJX Watch: Who It's For
The ZJX Watch goes the opposite direction: it's a wearable that happens to include earbuds. The pitch is a 2-in-1 — a fitness tracker and a wireless earbud setup combined into one device for "seamless connectivity and audio experience." The watch side is a round, precision CNC metal body in a silvery green finish with a green band, and a 1.52-inch full-touch HD screen that the data sheet says stays readable in outdoor environments. That's a meaningful detail if you run, hike or walk outside and want to check data in daylight.
On the health and fitness side, it tracks steps, distance, calories burned and heart rate, supports multiple sport modes, and adds a sedentary reminder to nudge you when you've been sitting too long. It pairs with your phone over Bluetooth to surface calls, messages and app notifications on your wrist, and it includes GPS geotagging via your smartphone — meaning it leans on the phone for location rather than carrying its own satellite chip. The battery is a 400mAh lithium-polymer cell, which is a much bigger capacity than a pair of earbuds — expect it to serve as the power backbone for the whole 2-in-1 setup.
The audio half is described as "9D Bluetooth headphones" for an immersive listening experience, and the package includes the smartwatch, the Bluetooth earphones and a charging cable. It's aimed at unisex adults, and the marketing leans toward fitness enthusiasts and outdoor explorers.
Side-by-Side: Which Should You Choose?
• Best for pure audio quality focus → Lenovo LP40. A 13mm dynamic driver with AAC/SBC decoding and a 20Hz–20KHz range is a dedicated audio design.
• Best for fitness and health tracking → ZJX Watch. Steps, distance, calories, heart rate, multiple sport modes and a sedentary reminder.
• Best for wrist notifications → ZJX Watch. Calls, messages and app notifications land on the 1.52-inch screen.
• Best for calls and voice clarity → Lenovo LP40. A microphone in each earbud plus intelligent noise reduction designed for stereo-mode calls.
• Best for outdoor visibility → ZJX Watch. The HD display is specified as clearly visible in outdoor environments.
• Best for one-ear use / flexibility → Lenovo LP40. Use either bud alone or both together.
• Best for a single-gadget setup → ZJX Watch. Watch, earbuds and charging cable come in one package — fewer things to keep track of.
• Best for battery convenience → Lenovo LP40. 5 hours per earbud session and a 250mAh case that stores and recharges them in about 1.5 hours.
In my opinion, the Lenovo LP40 is the safer buy for most people, because most people comparing these two already know they want earbuds — and the LP40 is a focused, well-specified pair with Bluetooth 5.1, dual mics, touch controls and a charging case. I'd pick it if my day is about music and calls. I'd only choose the ZJX Watch if the watch half genuinely matters to me — notifications on my wrist, step and heart-rate tracking, and the convenience of a 2-in-1. That's a real need, just a narrower one. Decide which half of the ZJX's feature list you'd actually use daily; if it's the watch, buy the ZJX. If it's the sound, buy the Lenovo.
FAQ
The data sheet describes the earbuds as integrated TWS sports earbuds that pair over Bluetooth, and the package includes them separately from the watch, so they're designed to work as Bluetooth earphones. Pairing behavior with the watch itself is worth confirming with the seller.
Up to 5 hours of music per earbud, and the 250mAh charging case stores and recharges them. A full earbud charge takes about 1.5 hours.
The ZJX Watch. It's the only one of the two with step, distance, calorie and heart-rate tracking, sport modes and a sedentary reminder. The Lenovo LP40 has none of those features.
Both are sold on Amazon, and pricing changes often, so check the current price on Amazon using the button on this page rather than relying on any figure you've seen elsewhere.
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