Can be directly inserted into the card for use. In fact, phone watches, like mobile phones, are all used by inserting phone cards, but their expressions are different. One is a watch, and the other is a mobile phone, but they can all make phone calls, and even some phone watches can download various apps, such as QQ and WeChat.
Sim cards generally need to be moved or connected. At present, many children's smart watches do not support the version of telecom cards, and sim cards also need to be enabled with data traffic function, which depends on the requirements of various brands.
Extended materials:
There are two kinds of SIM cards with the same function but different shapes in actual use:
1, embedded SIM card (commonly known as small card), the size of this card is only 25mm× 15mm (smaller than ordinary stamps), which is a semi-permanent card installed in GSM mobile phones. It is the most popular SIM card at present. If you want to change a small card into a big card, you only need to buy a Cato, and the small card can be used as a big card.
2. card SIM card (commonly known as big card). The size of this card is 54mm×84mm (about the size of a business card). Similar to the IC card, the large card conforms to the ISO78 16 standard for IC cards. Users can use the card by inserting it into the mobile device.
References:
Baidu encyclopedia-children's watches