Hi everyone, I have a problem with the time in my phone. I have set it one day through the "Set time automatically" button in Settings>System>Date & time. After a few weeks I realized that my time wasn't up to date (I was a few minutes "faster" than real time).
So I turned "Set time automatically" on again, the time turned right and I turned "Set time automatically" off.
After a few weeks my time was wrong again.

I don't want that my phone cheks the time all the time when I'm in WiFi so I don't want to activate "Set time automatically" permanently.
But its also not good that my time changes without me knowing it.

Can anyone help me or does anyone know what causes these issues?

Hi there, time updates are done on GrapheneOS in a more secure way than on stock Android. For more details, please see the following details from the FAQs. It's security sensitive to keep the time set accurately, and therefore it's recommended you enable the toggle to update the time automatically.

An HTTPS connection is made to https://time.grapheneos.org/generate_204 to update the time with a millisecond precision X-Time header. As part of future support for using other services, it falls back to the standard Date header with second precision.

This is a full replacement for Android's standard network time update implementation, which uses unauthentication SNTP (Simple Network Time Protocol) with fallback to the cellular network when it's not available (GNSS can also be used as a time source but is disabled by default, and OEMs can choose the priority order). Network time updates are security sensitive since certificate validation depends on having an accurate time, but the standard NTP / SNTP protocols used across most OSes have no authentication or encryption.

We plan to offer a toggle to use the standard functionality instead of HTTPS-based time updates in order to blend in with other devices.

Network time can be disabled with the toggle at Settings ➔ System ➔ Date & time ➔ Set time automatically. Unlike AOSP or the stock OS on the supported devices, GrapheneOS stops making network time connections when using network time is disabled rather than just not setting the clock based on it. The time zone is still obtained directly via the time zone provided by the mobile network (NITZ) when available which you can also disable by the "Set time zone automatically" toggle.

https://grapheneos.org/faq#:~:text=An%20HTTPS%20connection,NTP%20/%20SNTP%20protocols

    treequell

    I use my phone mostly in public WiFi and because of that I thought that it would be better to disable automatic time setting so the doesn't ask for the service all the time.

    • de0u replied to this.

      sleep_legacy I think the key issue is that phones generally are set up to correct time from some network source because they don't keep time very well on their own. So in practice your options may be accurate network-corrected time versus inaccurate time. Note that TOTP authenticators need fairly accurate time.

      For the moment you could briefly enable network time a couple times per day on a trusted network.