Download APK Installer on your Android phone or tablet and open the APK Installer app.
Open APK Installer, and then click on INSTALL.
Tap ALLOW.
Select the files you want to install: zip, .xapk, .apkm, .apks and tap OK.
Tap INSTALL.
Tap ALLOW.
Follow the steps above, and the file will be installed on the Android phone or tablet successfully.
Download & install APK Installer.
Search this app on the website.
Tap OK and begin to Install APK Installer.
Tap INSTALL.
Tap SETTINGS.
Find UNKNOWN SOURCES on the list, and then tap TURN ON.
Tap OK.
Make sure UNKNOWN SOURCES remains TURN ON and allow installation of app from unknown sources.
Tap OK.
Follow the steps above, and you will download & install APK Installer successfully.
Settings » About phone » Tap MIUI version (Tap 7 times to enable developer options).
You need to install the APK Installer
Open the APK Installer app » Settings » Open Developer Settings » Turn off MIUI optimization » This setting will take effect after you reboot your device.
Download APK Installer on your Android phone or tablet and open the APK Installer app.
Find SETTINGS on the list below, and then open it.
Find Turn on MIUI optimization on the list.
Then click on TURN OFF.
Tap TURN OFF and then you will Turn off MIUI optimization.
Make sure MIUI optimization remains TURN OFF.
This setting will take effect after you reboot your device.
Settings » Additional Information » Privacy » Turn on Unknown sources
Find SETTINGS on your Android phone or tablet.
Open ADDITIONAL SETTINGS on the list.
Find PRIVACY.
Find UNKNOWN SOURCES on the list, and then tap TURN ON.
Tap OK.
Make sure you turn on UNKNOWN SOURCES.