We have contained the official link to download the True Smart 4.0 Unlock Firmware (Flash File) on your Computer. This firmware comes in a zip package, which means you have to extract it using any unpacking tool like 7-Zip or WinRAR.
True Smart 4.0 Unlock Firmware (Flash File) Download
File Name: True_Smart_4.0_MT6572_V12_20150519.zip
Firmware – Download
[*] Take a Backup: If you are going to flash the above Firmware on your True Smart 4.0, then take a backup of everything as because your personal data will be deleted after flashing the stock ROM.
[*] The firmware shared on this page is officially released by the company and helps you to recover your device if you ever got bootloop, software error, update error, hanging and dead issue.