Retroid Pocket 2 – Android 8.1 Install Guide

Last updated: 02JAN2021 (see Changelog for details)

After months of promises, a rescinded update, and a very patient Retroid Pocket 2 community, we finally have the Android 8.1 update that has been in the works since August.

I have to say that this operating system update does wonders for the UI lag issues that were prominent in the original Android 6.0 OS, and it has breathed new life into my device. So I decided to document my upgrade experience so that you could easily follow the steps. Please note that you will need a Windows PC in order to run this update, because we will be using .exe and batch files, which won’t run on MacOS. If you are a Mac user, check out my guide on how to run a virtual Windows machine.

Table of Contents
What's new in Android 8.1
Download the necessary files
Install required drivers
Back up your save/config files
Update the OS
Reinstall the stock apps
Notes

Changelog

What’s new in Android 8.1

In addition to a new interface and other Android-related updates, here are the developer’s notes related to the Retroid Pocket 2:

1. Open Android upgrade to 8.1
2. Because the system partition in the original partition table was too small, 8.1 could not run normally. We decided to adjust the partition table and expand the Android system partition to 1GB, and support root. This upgrade needs to be formatted.
3. Fix 8.1 battery measurement problem.
4. boot.img No encryption, so LK followed up the change accordingly.
5. Other parts follow up the latest revision.
6. 8.1 upgrade with independent channel, separate from 6.0. Upgrade across Android versions is not supported.
7. Open Android 8.1 SDK source code. Anyone can build and customize their own Android system based on the latest official version.
   https://drive.google.com/file/d/1mZ-9kBCQwI9w4ulbOzqH4QX3EbJiafTF/view?usp=sharing

Also note that the ClassicBoy app is not supported in Android 8.1.

Download the necessary files

Note that these install files were found in the Retroid Handhelds discord server. If you’re not already a member, be sure to check it out — there you can find a wealth of knowledge and specific channels for technical assistance.

You’re going to want two to download two different files, and they are each about a GB each and found in this folder.

Retroid Pocket 2 8.1 v2 with Guide: This file contains all of the files you’ll need to install the latest Android 8.1 operating system to the Retroid Pocket 2. Once you’ve downloaded it, unzip the file onto your computer.

8.1 Stock Apps: This update will wipe all of the contents off your device, and so this file contains all of the necessary files to re-install all of the default apps and emulators on your Retroid Pocket 2. Once you’ve downloaded this file, also unzip it onto your computer. Note that if you use your SD card as internal storage, you will need to use the “internal” zip file (and follow the instructions in that guide. This guide is for those who don’t use their SD card as internal storage. Note that in the video, I used a file called “SD Card Backup V3” — this is the same file, but updated and with a different file name.

Install required drivers

In order to flash your firmware, your RP2 and PC need to properly communicate. You will accomplish this by installing the required drivers. Here are the instructions from the Retroid Handhelds discord server:

Download this zip file, extract it then right click on andrdoid_winusb.inf and click install.
These drivers will allow you to use SPFlash.
MAKE SURE YOU REBOOT YOUR PC AFTER YOU INSTALL THESE DRIVERS

Back up your save/config files

This install is going to wipe your internal storage, but your external SD card should remain intact. But most of your save files and configuration files are found on the internal storage.

To access your internal storage, plug your Retroid Pocket 2 into your PC, then on the RP2 drag your mouse cursor from the top and find the “USB for charging” section, then click on it and select “File transfers”. The internal storage should now show up on your Windows PC, and you can navigate to the folders you want to copy the save files and move them onto your PC for safe keeping. Also, if possible, use a USB 2.0 port on your computer instead of a USB 3.0 port. This step seems to be the biggest hurdle for most users — make sure that your PC recognizes your device, because it is needed for the SPFlash flash_tool.exe file a couple steps down.

Finding your save files is pretty easy — just go to that emulator’s folder, and then find the save files. You may have to do a bit of digging, but they’re all pretty easy to find.

If you plug in the device and it isn’t recognized by your PC, install these preloader drivers and try again. If that still doesn’t work, go into the Windows Device Manager and change the device to be recognized as a generic Microsoft “USB to Serial” device. I’ve also read reports that you may have to enable “USB debugging” on your device in order to connect. I didn’t have to do any of these things, but other users may have to.

Update the OS

To start, make sure that your Retroid Pocket 2 is still connected to your PC for file transfer (like in the previous step). Go to the RP2 install folder that you downloaded, and go to the “RP2 Key Backup Tools” folder. There you will find the ADBDriverInstaller.exe file, go ahead and open that up and click the “Install” button on the bottom-right corner. It may tell you at the ADB driver is already installed, which is fine. Close this app.

Your device has a special “keyfile” which allows you to access the Retroid Operating System. We need to back up this key so that you won’t have issues in the future. In that same folder, and while your device is still connected to the PC via USB, click on the RP2 Key backup.bat file. This will run a simple script. In that same folder you should see a “device_key” file — verify that the file’s creation time is the current time, and you’re good to go.

POWER OFF your device and unplug it from your PC.

In your RP2 install folder, go to the SPFlash folder, and run the flash_tool.exe file. You may get a notice pop up, just click “OK”. In this app you will see a few different folder locations. Select the following files for these folder locations:

Download-Agent: SPFlash/MTK_AllInOne_DA.bin
Scatter-loading File: Android8.1_V2/MT6580_Android_scatter.txt

In the dropdown menu to the left (that says “Download Only”, choose “Format All + Download”.

Next, click the Download button near the top left of the app. While your RP2 is still powered off, plug it into your PC and it will download and flash the new operating system onto your device.

If SPFlash fails with errors consistently, go into Device Manager, hit View and go down to show hidden devices. Navigate down to the Ports (COM & LPT) section and open it. Right-click on Mediatek DA USB VCOM and hit uninstall. Then check the box that says to delete the driver and press OK. Repeat the uninstallation for any Preloader USB VCOM items in that list as well. They may not have deletion checkboxes. That is ok. Then go into the folder that had the installer for the MTK Preloader drivers and open the folder that is appropriate for your computer. For most users it will be the Win764_Driver. Right-click on the .inf file (ex: usb2ser_Win764.inf) and hit install. Reboot your PC and try flashing again.

UNPLUG your device from the PC, and turn it on. It will boot into the Retroid OS interface. Press and hold the HOME button for a few seconds, then select “Switch system” to boot back into Android. Once you’re in Android, plug the RP2 back into your PC. and then on the RP2 drag your mouse cursor from the top and find the “USB for charging” section, then click on it and select “File transfers”.

Go into the “RP2 Key Backup Tools” folder on your PC again, and this time run the RP2 Key restore.bat file. This will load your device_key file into the device so that you can access the Retroid OS. After it’s installed, the RP2 will reset itself.

Reinstall the stock apps

Now we’re going to use the “Stock Apps 8.1v2 internal with Guide” folder to install the stock apps back onto your device. POWER OFF your device and eject the SD card, then plug it into your PC using a USB SD card adapter. You could technically use the USB interface to transfer the files over to your SD card via USB, but it’s slow and unreliable for large transfers like this. It’s better to use the SD card directly.

Move over the “preinstall” folder and the internal_preinstall.sh file from the “Stock Apps 8.1” folder onto your sd card. If your SD card is missing any of the other folders or files found in the “Stock Apps 8.1” folder, go ahead and move those over as well. Eject your SD card and put it back into your device, and power it back on.

On the device, go to the Toolbox app, then select “Execute script”. Locate your SD card by clicking on the menu on the top-left, and then find the internal_preinstall.sh file and click on it. It will then install your default apps and reboot your device. Congratulations, you’re done!

Notes

Some quick notes:

• I would guess that this new Android OS interface is about 25% faster than the previous Android 6.0, and that’s a significant boost in the user interface.
• You will need to setup your network again (both in Android OS and in Retroid OS).
• You will need your network set up in order to add the Retroid OS to your apps. Once connected to a network, go to Toolbox > Install Retroid Pocket app, and the app will download, install, and appear with the rest of your apps.
• In order to access the Google Play Store, you will need to go into the Toolbox and select “Enable Google Apps”.
• The Retroid OS app has had some significant updates, including a robust settings menu for games that includes aspect ratio and shaders options. I’m not sure how long this OS has had this update, since it had been a while since I booted it up. But these are some welcome changes.
• The Mupen64Plus FZ app will default back to 320×240 resolution, which makes your Nintendo 64 games look pretty terrible. You can change it back to 640×480 in the options menu.
• PPSSPP seems to work best with an auto frameskip set to 1.
• SteamLink seems to show games at full aspect ratio, but this may have been because I tested it with an older game (GTA3).

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Changelog

02JAN2021
– updated guide with new files and instructions from Retroid Handhelds

29DEC2020
– published guide
– added preloader drivers link
– added Google Apps note

30DEC2020
– added preloader comments