The quick answer.
Lagenio 4G Kids Smart Watch K3 (Black + Blue / US) is a kids smartwatch watch with case dimensions 51.2 × 42.8 × 15.5 mm (as listed by Lagenio) at $99.99. We recommend it for families who want parent-managed calls, SOS and location functions on a watch, with two strap colors in the selected option.
Why it belongs on the shortlist.
The K3 is built around family contact rather than a general app library: Lagenio lists 4G calls, video calls, group chat, SOS and location features. We like the practical flexibility of the Black + Blue option, which includes two straps, and the 770 mAh battery is a useful published figure when comparing kids’ watch phones. Lagenio also says the watch has no open app store or social media apps.
A family-contact watch with a clear purpose.
The K3 brings 4G voice and video calls, group chat, SOS and location features together in a child-focused watch. Lagenio lists GPS, Wi-Fi, LBS, A-GPS and accelerometer positioning. That gives parents several ways to use the watch for day-to-day contact, while the exact location result can depend on the available signal and surroundings.
Two straps and a changeable look.
Lagenio lists blue and black straps with this color combination and describes the housing as changeable. That gives the K3 two ready-to-wear looks without buying a separate band. The 51.2 × 42.8 × 15.5 mm body is substantial on a child’s wrist, so compare the full footprint with a watch the child already wears.
Plan for the physical SIM.
The K3 uses a physical 4G Nano SIM with voice and data, and Lagenio says eSIM is not supported. The US version arrives with an inactive SpeedTalk SIM; activation is optional at $15.99 per month, or you can use another compatible SIM. Lagenio lists SpeedTalk, T-Mobile and AT&T for the US K3, but confirm the exact plan before ordering.
Display, battery and water guidance.
Lagenio lists a 1.7-inch, 240 × 280 pixel display and 770 mAh battery. The product is rated IP68 for everyday splashes, but the brand recommends removing it before bathing or swimming.
Price and reader offer.
Lagenio listed the US K3 at $99.99 USD on October 20, 2026, with $109.99 shown as its original price. The supplied Watch Ritual code is SEBASTIANBASSOL for 10% off; eligibility on this exact option has not been tested, so check the final order summary.
The details, at a glance.
- Selected option
- Black + Blue · US version · variant 50753540129054 · two straps included
- Case and display
- 51.2 × 42.8 × 15.5 mm · 1.7-inch, 240 × 280 pixel display
- Memory and camera
- 128 MB ROM · 64 MB RAM · 0.3 MP camera
- Connectivity
- 4G voice and video calls; physical 4G Nano SIM with voice and data
- SIM support
- No eSIM; Lagenio says a physical Nano SIM is required
- Location
- GPS, Wi-Fi, LBS, A-GPS and accelerometer positioning, as listed by Lagenio
- Safety and contact
- SOS, parent-managed contacts, voice/video calls and group chat
- Battery
- 770 mAh, as listed by Lagenio
- Water use
- IP68 for everyday splashes; Lagenio recommends removing it before showering, bathing, swimming or entering the sea
- Case dimensions
- Not specified by Lagenio on the product page
- Current sale price
- $99.99 USD; Lagenio displays $109.99 as the original price, checked October 20, 2026
- Reader code
- SEBASTIANBASSOL · 10% off supplied for Lagenio; exact K3 option not cart-tested
What draws us in
- Voice and video calls, SOS and location features are grouped around family contact
- The selected Black + Blue option includes two straps
- A 1.7-inch display and 770 mAh battery are specified by Lagenio
Before you choose
The K3 needs a physical 4G Nano SIM with voice and data for its connected functions; it does not support eSIM. The US version includes an inactive SpeedTalk SIM that can optionally be activated for $15.99 per month, or replaced with another compatible SIM. At 51.2 × 42.8 × 15.5 mm, it has a substantial footprint for a child. Lagenio lists IP68 for everyday splashes but advises removing it before swimming. The supplied SEBASTIANBASSOL code is 10% off for Lagenio, but its eligibility on this exact K3 option has not been checked.
Who it suits.
Families who want parent-managed calls, SOS and location functions on a watch, with two strap colors in the selected option.
When to choose something else.
Choose a different model if you need eSIM, a watch that works without a mobile plan, or published case measurements before purchase.
Warranty, returns and ownership.
Lagenio lists a 30-day return period and a one-year limited warranty. Review the current terms and confirm the selected US version, SIM compatibility and any mobile service cost before ordering.
Closest alternatives.
- Lagenio K9 4G AI Kids Smart Watch (Purple / US): The K9 is the step-up US option with a 1.78-inch AMOLED screen and 5 MP camera, if those extra features matter more than the K3’s simpler package.
- Lagenio K10 AI 4G Kids Smart Watch (Blue / EU/UK): The K10 is a separate EU/UK model with a larger listed battery; confirm its regional delivery and SIM compatibility before choosing it.
Think beyond the diameter.
The published case dimensions are 51.2 × 42.8 × 15.5 mm (as listed by Lagenio); use that complete footprint and thickness to judge fit. Compare the case with a watch the child already wears and compare the proportions with a watch you already enjoy wearing.
Lagenio partner code and offer terms. Our supplied code is SEBASTIANBASSOL for 10% off. Check the exact model and variant at the store, then confirm eligibility and the final total at checkout.
Where to buy.
Specifications and product photography: Lagenio K3 US product page (checked October 20, 2026). Find 4G Kids Smart Watch K3 (Black + Blue / US) at Lagenio through our partner link and search for the selected option there. How we choose.
A few good questions.
What is the discount code for the Lagenio 4G Kids Smart Watch K3 (Black + Blue / US)?
The Lagenio discount code is SEBASTIANBASSOL for 10% off at watch.lagenio.com. We have not tested it on this exact model, so confirm the saving in your order summary. Every code and tested price: https://watchritual.com/promo/lagenio
What does the Lagenio 4G Kids Smart Watch K3 (Black + Blue / US) do?
Lagenio lists 4G voice and video calls, group chat, SOS, parent-managed contacts and location features using GPS, Wi-Fi, LBS, A-GPS and accelerometer positioning.
Does the Lagenio 4G Kids Smart Watch K3 (Black + Blue / US) need a SIM?
Yes. Lagenio specifies a physical 4G Nano SIM with voice and data. The K3 does not support eSIM, so confirm carrier compatibility and plan costs before ordering.
How many straps come with the Lagenio 4G Kids Smart Watch K3 (Black + Blue / US)?
Lagenio lists blue and black straps for the selected Black + Blue option.
How much is the Lagenio 4G Kids Smart Watch K3 (Black + Blue / US), and what is the reader code?
Lagenio listed the US option at $99.99 USD on October 20, 2026. The supplied Watch Ritual code is SEBASTIANBASSOL for 10% off; the exact option has not been cart-tested, so confirm eligibility and the final total at checkout.
What are the case dimensions of the Lagenio 4G Kids Smart Watch K3 (Black + Blue / US)?
Lagenio lists dimensions of 51.2 × 42.8 × 15.5 mm and a 1.7-inch display.
