RTC Tool

リアルタイムクロック（RTC）は、デバイスのクロックである。

A real-time clock (RTC) is a computer clock (most often in the form of an integrated circuit) that keeps track of the current time. Although the term often refers to the devices in personal computers, servers and embedded systems, RTCs are present in almost any electronic device which needs to keep accurate time

This app for testing device click difference between device clock and network time.

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