How to update Blackview smartphone's software by TF card?
Step1:Copy the file update,Zip in the TF card,then power off,Push the volume up button and power on button at same time,until the below image show up.

Step2:Push power button one time quickly,enter the menu,and choose the 4th option"wipe date/factory reset"by volume button like below.Then press the volume up button,after entering the menu,choose"delete all user date".

Step3:Press volume down to choose the 5th option"wipe cache partition",then press the volume up button.

Step4:Under menu,press volume down,choose the second option"apply update from sd card",press the volume up button.

Step5:The device will enter TF card,please choose"Update.ZIP" like below image.
Step6:Press the volume up button to verify tochoose ZIP file.

Step7:Press the volume up button to start the update,like below image.

Step8:wait until below image show up which means updating finishing.Choose"reboot system now"and reboot the device,the updated system begins.