After the Xiaomi 3 system is updated, you can't enter the SMS setting by pressing the left key.

After MIUI6, the system enters the SMS setting step:

Enter System Settings-System Application

Enter short message

After MIUI6, the system will reset the button function, and click the menu button in the lower left corner to enter the memory clearing by default.

Users can also customize:

Enter System Settings-Other Advanced Settings

load key

Set related key functions.