How to uninstall Lonsdor K518S / K518ISE APK?


Here is the Solution to Some Common Problems of K518
If your  Lonsdor K518S / K518ISE device met those problem:
Problem 1: Cannot enter the main interface of the device. 
Problem 2: It takes a long time to enter the main interface of the device.
Problem 3: Some menus are lost in the device 

Here is the solution to fix all above problem:
 Lonsdor K518S  APK
Hold those two buttons marked in red at the same time, and you will enter the interface below.
 Lonsdor K518S  APK
Press “Uninstall APK” once, and you will enter the interface below. 
 Lonsdor K518S  APK
Press “OK” and you will enter the interface below again.
 Lonsdor K518S  APK
Press “Oldest APK” once and you will enter the interface below. 
 Lonsdor K518S  APK
 Lonsdor K518S  APK
Enter the password and you will see the interface below. Connect the device to WiFi and then press “
 Lonsdor K518S  APK
Press “OK” to update the device. 
 Lonsdor K518S  APK
The device will be normal as before after updating.