On: One second per second is harder than it sounds

[pjc50]

GSM phones are supposed to be able to pick up "NITZ" (network information and time zone") messages, but these aren't reliably sent by most networks. In practice, smartphones get it over NTP like everyone else and dumbphones have user-set time that may, if you're lucky, be synced by counting the base station's time slot intervals.

[easytiger → pjc50]

Yes modern smartphones often hardcode ntp servers and prob do ineffective hard resetting. Would be good to know more how they do it.

[enf → easytiger]

Things have changed a bit since the last time I had anything to with it, but you can read the Android source code: https://github.com/android/platform_frameworks_base/blob/mas...

NITZ is terrible. You only get one-second accuracy, a GMT offset, and a DST flag, and they can all be wrong at the whim of someone at the phone company.