NTP time synchronization is used to provide an accurate base for our content synchronization.
NTP (Network Time Protocol) synchronization works automatically if the server (that the device is connected to) has an NTP server. If the server does not have an NTP server, or the connection loses between the device and the NTP host, then the device will search for other time sources, like Wallboard server system time.
The device requests a new timestamp from the NTP server every 2 minutes to ensure content synchronization is accurate. In theory, it would be enough to synchronize the time only once. However, sometimes the time on Android devices can deviate so it has to be refreshed regularly in order to have the most accuracy.