Wondering whether a kids smartwatch sim card is really necessary, or if there’s a way to skip that step entirely? Short answer: for any 4G kids watch that makes calls or shows live location, a SIM card is not optional — here is exactly what that means before you buy.
This guide covers what a kids smartwatch SIM card does, which REXQU models need one, and how to pick a plan that actually works with the watch.
Why a Kids Smartwatch SIM Card Is Required
Every REXQU 4G kids watch — the KidGuard Pro, KidTrack and KidView — connects to the cellular network the same way a phone does, through a nano-SIM card with an active data and calling plan. That connection is what powers video calls, live GPS location in the parent app, and one-press SOS alerts. Without a SIM, the watch can still keep time and track steps, but calling and real-time location will not work.
REXQU KidGuard Pro vs KidTrack vs KidView: SIM & Data Compared
| Feature | KidGuard Pro | KidTrack | KidView |
|---|---|---|---|
| SIM required | Nano-SIM, 4G | Nano-SIM, 4G | Nano-SIM, 4G |
| Video calls | Yes | Voice + data | Yes |
| Location tracking | GPS/WiFi/LBS, history routes | GPS/WiFi/LBS, safe zones | GPS/WiFi/LBS, safe zones + history |
| Battery | 750mAh, 1–2 days active use | 700mAh, up to 7 days standby | 700mAh, up to 7 days standby |
| Water resistance | IP67 | IPX7 | IPX7 |
| Price | $109.97 | $89.97 | $99.97 |
The REXQU KidGuard Pro is built for the biggest battery and the widest feature set in the range. The REXQU KidTrack is the featherlight option at 47 grams if your child is younger or smaller-wristed. The REXQU KidView adds the biggest screen, a 1.83-inch display, if your child will look at it as much as they wear it.
Choosing a SIM Plan That Works
The SIM itself is not included with any REXQU kids smartwatch — you supply it from your own carrier. Before buying a plan, confirm two things with the carrier: that the plan supports a kids or IoT-style device (some carriers have a dedicated low-cost tier for these), and that the SIM’s 4G LTE bands match what the watch supports in your region. Most major US carriers and their prepaid sub-brands offer a compatible plan.
A nano-SIM is the same physical size used in most modern phones, just installed in a smaller tray. For general background on how this technology works across devices, see the Wikipedia entry on SIM cards.
Frequently Asked Questions
Is there a monthly fee from REXQU for a kids smartwatch SIM card setup? No — the parent app is free with no REXQU subscription. The only ongoing cost is whatever SIM plan you choose from your own carrier.
Can I use an old phone’s SIM card? Only if it is already a nano-SIM sized for a phone and on an active plan that supports data and calling; otherwise your carrier can issue a new nano-SIM on the same account.
What happens if I don’t insert a SIM? The watch still functions as a basic wearable — timekeeping, activity tracking and alarms work — but calling, live location and video calls will not, since those all route through the cellular connection. Most families find the calling and location features are the whole point of buying a kids watch over a basic activity tracker, so it is worth confirming SIM compatibility before checkout rather than after the watch arrives.
See the full range on the REXQU kids smartwatches page to compare features side by side before you buy a SIM plan.
Bottom Line
A kids smartwatch SIM card is a requirement, not an accessory, for any REXQU 4G model — it is what turns a step counter into a real safety device with calls and live location. Confirm carrier compatibility first, and the rest of setup takes just a few minutes.