The Time Zone Data module updates daylight saving time (DST) and time zones on Android devices, standardizing both the data (which can change frequently in response to religious, political, and geopolitical reasons) and the update mechanism across the ecosystem. For more details on Time Zone Data, see Time Zone Rules.
Changes in Android 10
Android 10 deprecates the APK-based time zone data update mechanism (used in Android 8.1 and Android 9) and replaces it with an APEX-based module update mechanism. AOSP continues to include the platform code necessary for APK-based updates, so devices upgrading to Android 10 can still receive partner-provided time zone data updates through APK. However, the APK update mechanism shouldn't be used on a production device that is also receiving module updates, as an APK-based update supersedes an APEX-based update (that is, a device that receives an APK update ignores APEX-based updates).
Format and dependencies
The Time Zone Data module is distributed as an APEX file.