[Android General] wishie197:
On to the 4-inch version

This unit had similar problems (no Play Store and outdated WebView implementation) but it was a bit more of a mess to deal with.

Installing the Play Store

Unlike the 7-inch version, you cannot simply install the APKs and expect it to work. Google Play Services will repeatedly crash and logical shows this is due to a missing MANAGE_USERS permission.

Like the 7-inch version, there is no custom recovery available for this unit, so flashing something like OpenGApps in the normal fashion is not possible either. Unpacking the OpenGApps zip and attempting to run the installer script within is also a dead-end as it requires the 'ash' shell that is not available on the device. But never fear, I got things to work.. here is how:

First we need to enable 'USB Debugging' which can be found in 'Developer options' part of the Settings app within Android.

Open 'Settings' app, by swiping down from the top of the screen and long-pressing the Wi-Fi icon.

This will load the settings app on the Wi-Fi page

Press the 'hamburger menu' and scroll down and select 'About device'

Once there, look for 'Build Number' and quickly tape on it 10 times or so until you see 'You are now a developer'

Click on the 'hamburger menu' again and you should now see a new 'Developer options' section.

Inside 'Developer options' there is a setting labelled 'USB debugging'. Enable it.

Connect your tablet to your PC using a micro-USB cable.

This is where things get a bit different. I had to unpack the OpenGApps zip file, unpack the lzip archives inside that, and figure out where all the files are meant to go so we can manually graft them into the /system/ folder on the device. You can download the ready-to-go folder here.

If you're the kind of person who wants to do it themselves, I have attached a directory tree structure to this post that shows where the files need to be.

As with the 7" version, we are going to use ADB to get these files onto the unit.

Copy the files onto the device

adb push opengapps-4inch.tar /sdcard/Download/

Open an adb shell

adb shell

and switch to root by typing

su

Remount the /system filesystem

mount -o rw,remount /system

Unpack the opengapps-4inch.tar file

cd /
tar -xvf /sdcard/Download/opengapps-4inch.tar

That should be it. Reboot and check that the Play Store is now available on your device.

Updating (Installing alternative) Android WebView

Just like the 7-inch version above, we do basically the same thing, but we have to use a different version of the Xposed Framework suitable for Android 7.1.2

Download the xposed-v89-sdk25-arm.tar from here

Download the XposedInstaller_3.1.5.apk attached to the first post. We can use the same version of this app.

Use adb on your PC to copy it to the device

adb push xposed-v89-sdk25-arm.tar /sdcard/Download/

Use adb on your PC to install the XposedInstaller apk

adb install XposedInstaller_3.1.5.apk

Open an adb shell

adb shell

and switch to root by typing

su

Remount the /system filesystem (needed if you rebooted after installing Play Store)

mount -o rw,remount /system

Extract the xposed-v89-sdk25-arm.tar file

tar -xvf xposed-v89-sdk25-arm.tar

Change into the directory that was just created

cd xposed-v89-sdk25-arm

Make the installer script executable

chmod a+x flash-script.sh

and run it

./flash-script.sh

Xposed Framework is now installed, but not activated. Reboot your device. Please note, it will take longer to boot than usual on the first boot.

Once your device has rebooted, open the Xposed Installed app and make sure it is activated. If it's orange and says its not activated, another reboot should sort it.

Once you have confirmed it is activated, we need to install a module called 'Any WebView'. Click on the Hamburger Menu, tap 'Download' and use the search to look for an install 'Any WebView'. Reboot your device.

Now, we need to install an updated Android WebView. You can install any compatible webview such as 'Google Chrome' or 'Android WebView' from the Play Store.

Go back into Settings->Developer options, select 'WebView Implementation' and choose your newly installed WebView. Do not use 'Android System WebView 61.0.x' as it is outdated.

Congratulations! You can now install the HA app, Fully Kiosk app, or anything else you need from the Play Store.