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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want long battery life and a traditional in-ear fit for calls and gym sessions, choose iJoy Gravity TWS Earbuds; if you need an open-ear clip design that stays comfortable for hours and works with glasses, choose Kinglucky i21.
• iJoy Gravity TWS Earbuds — biggest strength: Bluetooth 5.0 with HSP, HFP, A2DP and AVRCP support, plus a claimed 30+ hours of battery life and a wireless charging case.
• iJoy Gravity TWS Earbuds — biggest trade-off: It's a sealed in-ear design with no active noise cancelling, so it blocks sound passively and may feel intrusive to anyone who dislikes tips in their ear canal.
• Kinglucky i21 — biggest strength: An open-ear clip-on shape at just 4.7g per bud, with Bluetooth 5.3 and a charging case that stretches total playtime to 45 hours.
• Kinglucky i21 — biggest trade-off: Only 6 hours of playtime per charge and an open design that lets ambient sound in by nature.
• Who iJoy Gravity TWS Earbuds is for: Buyers who want a familiar in-ear seal, long talk time and a low-latency connection for calls and workouts.
• Who Kinglucky i21 is for: Glasses wearers, small-eared listeners and runners who want nothing inserted into their ear canal.
The iJoy Gravity TWS Earbuds are the more conventional of the two — a rounded-tip, in-ear design in white with a plastic and silicone build. That combination of a soft silicone tip and a shape that follows the contour of the ear is exactly what keeps buds planted during movement, and it's the setup most people already know how to wear. If you've used in-ear buds before, there's no learning curve here.
Where it stands out is battery and connectivity. The spec sheet lists 30+ hours of battery life, with 30 hours of talk time and 20+ hours of standby, and the case carries a 300mAh battery that recharges the buds wirelessly on the go. A full case recharge takes about 1.5 hours and the buds themselves charge in about an hour. Bluetooth 5.0 with HSP, HFP, A2DP and AVRCP support means it pairs with essentially any Bluetooth source and handles in-call stereo audio and low-latency playback. For someone who takes a lot of calls or listens to podcasts all day, that's the real selling point.
Who should skip it? If you hate the feeling of silicone tips in your ears, or you wear glasses and find in-ear buds get dislodged by the arms of your frames, this isn't the shape for you. And because noise control is listed as none, anyone expecting active noise cancellation should look elsewhere — the in-ear seal is the only isolation you get. The IPX4 rating covers sweat and light splashes, not submersion.
The Kinglucky i21 takes the opposite approach: an open-ear clip-on. Nothing goes into your ear canal. The buds hook over the outside of your ear with an angled hook shape and weigh just 4.7g each, which is the whole appeal — the brand specifically calls out small ears and glasses wearers, and that's a genuinely underserved group. If you've ever had frames and earbuds fighting for the same real estate behind your ear, the clip-on format sidesteps that problem entirely.
On paper the i21 runs Bluetooth 5.3, which is a newer generation than the iJoy's 5.0 and brings the usual benefits: more stable connections, longer transmission range (listed at 10 meters) and better energy efficiency. Battery is a different story. You get 6 hours of continuous playtime per charge, extended to 45 hours total with the charging case, plus 90 hours of standby. The case takes about 1.5 hours to charge and the buds about 2 hours. IPX4 waterproofing with a nano hydrophobic coating means rain and sweat are fine.
The trade-off is baked into the design. Open-ear means you hear your surroundings — great for running near traffic, less great on a noisy train. There's no noise cancelling here either, and no in-ear seal to fall back on. The 6-hour single-charge figure is also modest compared to the iJoy's headline numbers, so heavy all-day users will be docking the buds in the case more often.
• Best for battery life → iJoy Gravity TWS Earbuds. 30+ hours of battery and 30 hours of talk time versus 6 hours per charge on the i21.
• Best for glasses wearers → Kinglucky i21. The clip-on format avoids the ear-canal and behind-the-ear crowding that in-ear buds create.
• Best for long calls → iJoy Gravity TWS Earbuds. The 30-hour talk-time figure and low-latency Bluetooth 5.0 profile support are built for voice.
• Best for running and outdoor sports → Kinglucky i21. Open-ear design keeps you aware of traffic, and each bud weighs only 4.7g.
• Best for a newer Bluetooth standard → Kinglucky i21. Bluetooth 5.3 versus 5.0, with a listed 10-meter range.
• Best for people who dislike ear tips → Kinglucky i21. Nothing is inserted into the ear canal.
• Best for people who want passive sound isolation → iJoy Gravity TWS Earbuds. The in-ear seal blocks more ambient noise than an open design.
• Best for total case capacity → Kinglucky i21. 45 hours total with the case versus roughly 30 hours of battery life on the iJoy.
In my opinion, the iJoy Gravity TWS Earbuds are the better buy for most people. The 30+ hours of battery life, the 30-hour talk time and the full Bluetooth profile support make it a more capable everyday companion for calls, podcasts and gym sessions, and the in-ear fit gives you at least some passive isolation. I'd only steer you to the Kinglucky i21 if the clip-on shape is the deciding factor — for glasses wearers, small ears or anyone who simply can't tolerate tips, the 4.7g open-ear design and Bluetooth 5.3 make it the smarter pick despite the shorter 6-hour playtime.
The iJoy Gravity TWS Earbuds list 30+ hours of battery life with 30 hours of talk time. The Kinglucky i21 lists 6 hours per charge, extending to 45 hours total with its charging case.
Yes — that's the core design intent. The open-ear clip-on shape sits outside the ear canal, so it doesn't compete with the arms of your glasses the way in-ear buds can.
No. Both list noise control as none. The iJoy Gravity TWS Earbuds rely on their in-ear seal for passive isolation, while the open-ear Kinglucky i21 lets ambient sound in by design.
For awareness of your surroundings, the open-ear Kinglucky i21 is the better fit and weighs only 4.7g per bud. The iJoy Gravity TWS Earbuds are also IPX4 sweat-resistant and shaped to stay put, so either works if you prefer a sealed in-ear feel. Check the current price on Amazon before deciding.
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