Here you can download MediaTek MT6735 based Scatter Stock Firmware for the Symphony Helio S1 Android device. The downloadable file High Compressed in an archive, You will get the Flash File after extraction. Included contains Flash Tool, USB Driver, and how-to Flash manual instructions.
[*] Chipset: MediaTek MT6753.
[*] Driver: MTK USB Driver.
[*] Flash Tool: Smart Phone Flash Tool.
Get Firmware for Symphony Helio S1 (Flash File)
Build Number: Helio_S1_1_XXX_V01.11_V2.0
Android Version: v5.1 (Lollipop)
Download Size: 1.34 GB
[*] Backup: During the flashing process SP Flash Tool will erase user data from the phone. So you need to backup for restoring those files on your device.
[*] Device Information: The Symphony Helio S1 phone powered by MediaTek MT6753 CPU. So you need to use MTK SP Flash Tool and MTK USB Driver to flash Firmware on this device.
[*] Flashing Information: You should use only the “Firmware Upgrade” option in SP Flash Tool when you want to reinstall or upgrade the Software of your device. – “Format + Download” option only for Engineering Purpose.