InfiniTime/doc/gettingStarted/time-nrfconnect.md

Syncing time

You must enable the CTS GATT server in NRFConnect so that InfiniTime can synchronize the time with your smartphone.

Launch NRFConnect, tap the sandwich button on the top left and select Configure GATT server:

Tap Add service and select the server configuration Current Time service. Tap OK and connect to your PineTime, it should automcatically sync the time once the connection is established!