While official changelogs for these specific Chinese-market head units can be difficult to find, community discussions on platforms like the 4PDA forums suggest the following improvements in the v8.1.1 series:
Firmware Over The Air: FOTA in Automotive Industry - Embitel
is a specific firmware version primarily associated with Android car head units powered by the Allwinner T3L (T3-P1) quad-core processor. This update is typically delivered via Firmware-Over-The-Air (FOTA) technology, allowing users to upgrade their vehicle's multimedia system wirelessly without a physical computer connection. Overview of FOTA v8.1.1
Use the built-in "System Update" application within the head unit settings.
If your device is experiencing extreme lag or "CarPlay" freezes, this firmware update may help, but it should only be performed if the version numbers match your specific hardware.
Before applying the v8.1.1 update, it is highly recommended to create a full system dump using an Android terminal.