Can smart phones replace children's watches?

System version upgrade is to optimize the original system. For the low version, the high version should theoretically run more smoothly and fix some bugs of the old version. Smart watches support the current mainstream Android and above, and the main reaction is to continue to connect and use the mobile phone after upgrading the system. But it doesn't mean that you can't use a lower version, just that the connection between mobile phones and peripheral devices is unstable. Generally speaking, the smartphone system connected by most smart external devices is not much different from the current mainstream system version, and everything can be connected. Pure hand tour, hope to adopt!