Smart watches phones for kids - what's inside?

Made in China, the following smart watches are sold under many different names.

I was trying to select a model with 4G/LTE support (as Vodafone will switch off 3G in 03/2021, see their press release) but this information is nowhere to be found on the user manuals.

4G Models

4G Watches are based on Spreadtrum/UNISOC chips, see this overview:

https://p.globalsources.com/IMAGES/PDT/SPEC/601/K1174402601.pdf

2G Models

2G Watches are based on Mediatek 2503DV chips.

FCC documentation 2AKM6-Q730 describes the following models:

Q730, Q750,  Q760, Q50, Q523, Q528, Q60, C1, C2, C3

says: "The electrical circuit design, layout, components used and internal wiring for above models are identical, only different in Model name."

A generic user manual for all these models is here.

FCC documentation 2AKM6-Q11 (2019-06-14)

External photos:

 

According to internal photos, the SoC used is MEDIATEK MT2503DV - ARMv7-based chip with GNSS (BeiDou,  Galileo,  GPS+GLONASS), Bluetooth 3.0 and 2G modem. RF frontend chip is RDA6625e quad-band power amplifier and antenna switch designed for GSM850, EGSM900, DCS1800, PCS1900 handheld digital cellular equipment.

Alternative mobile apps for management of these watches:

MyFrap!

https://findmykids.org/en

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