TrueNTP
Support
Answers to the questions the app itself can't fit. The in-app NTP Guide (Settings → NTP Guide) covers the concepts: stratum, offset, RTT, uncertainty, smearing, and more.
Why does the ± number never reach zero?
Honesty. A network round trip means true time can hide anywhere inside plus-or-minus half the round-trip time. TrueNTP reports that bound instead of pretending to a precision it can't have. On good wifi expect a few milliseconds; on cellular, more.
Why do readings jump around on cellular?
Cellular radio schedulers and carrier buffering inflate round-trip times and make the out-and-back legs unequal, which quietly absorbs error into the reading. The math can't see unequal legs. Trust trends over single readings on cellular, or use wifi for the tightest numbers.
A server shows RATE LIMITED
That server sent a "kiss of death" packet asking us to back off, and TrueNTP complies immediately. It usually clears after a while. Volunteer pool servers are far stricter than the big anycast services — consider a longer auto-poll interval if you see this often.
GNSS says "searching for satellites" forever
A first satellite lock typically takes 30–120 seconds with a clear view of the sky. Indoors it may never lock; near a window is hit or miss. If it reports "no raw GNSS on this chipset," your phone's GPS hardware doesn't expose raw measurements — nothing can be done in software, and NTP remains fully functional.
Does the location permission track me?
No. Android requires the precise-location permission to read GPS satellite time. TrueNTP uses it only to read the satellite clock; no position is computed, stored, or sent anywhere. See the privacy policy.
Contact
Bug reports, questions, feature ideas: . Include your device model and what the status lines showed — screenshots help.