Android Flashing Guide

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This document will guide you through the necessary steps needed to flash your Gemini with Linux or Android OS.

'Please note: 'Flashing Android or Linux will delete any user data on the device. Please make sure you have a backup of any important data before starting!

Important Note: please don’t use other tools to flash firmware fo your Gemini as it’s easy to loose key information such as the IMEI number. In particular, never use the “Format all + download“ option in the SP Flash Tool as this erases key information stored in the NVRAM partition and can lead to a non-functional device.

Download and Install FlashTool on Windows

The first step to install FlashTool on Windows PC is to install the flash tool drivers. These drivers are needed for your Windows PC to communicate with your Gemini, the minimum requirement is to have a 64bit Windows operating system.

You can find the drivers here: Windows Flash Tool Drivers

Once downloaded, unzip the archive. You will find a folder called FlashToolDrivers, open the folder and double click on the Install file. Allow the installation to complete by clicking Yes when asked to make changes.

Now that the drivers have been installed, you can download the Windows flash tool: Windows Flash Tool

Once downloaded the Windows flash tool. please unzip both it to reveal the FlashToolWindows folder. Next, run the flash tool by double clicking on flash_tool in the FlashToolWindows folder.

You will also need a firmware to flash, either Linux or Android. You can find the available Gemini firmware here: Gemini Firmware

Download and Install FlashTool on Linux

You can find the Linux flash tool software here: Linux Flash Tool

Building from source

You can also build the flash tool by yourself. You will find the source code

The tool is built using Debian 9.0

You will need a 64 bit Linux machine and you might need root access to run it. The executable file is If you get a BROM error when connecting the Gemini (see flash_tool console log) then you should follow this guide - specifically the 2 points regarding udev rules.

Configuring Flash Tool

Use the choose button as in the following screenshot to load the scatter file that you will find inside the downloaded firmware. In particular:

  • Downlad-Agent should be set to the file MTK_AllInOne_DA.bin, which is located in the FlashToolWindows or FlashToolLinux folder.
  • Scatter-loading file should be set to the specific scatter file of the firmware that you want to flash, which is located in the firmware folder


Backup the NVRAM partition

Before flashing the device with a different firmware it is a good idea to backup the current NVRAM partition. This partition stores key information for your Gemini, including the IMEI number. If it gets lost or damaged, your Gemini will not be able to take or receive calls.

The provided flash tool is already configured for your Gemini. To create a backup of your NVRAM partition, just click on the Readback tab and then on the Add button. A row will appear in the table as in the following screenshot.


Next, just click the Read Back button, connect your Gemini to your PC and restart the Gemini. Once rebooted, the flash tool will detect the phone and will write the NVRAM partition on a file on your hard disk called NVRAM0. It’s a good idea to keep this file as a backup.

Flashing the Gemini with an alternative firmware

Be sure to follow the previous step to store a copy of the NVRAM partition as backup. Now, run the Flash tool software and click on the Download tab. Next, locate the Scatter-loading File option and click on the associated choose button, as highlighted in the picture below:


Now, open the firmware folder from the firmware zip file you downloaded and select the scatter file.Each firmware package contains 2 firmware versions: Gemini_Android.txt can be used to flash a standard Android system, while Gemini_Android_Rooted.txt can be used to install a rooted Android version. You can also install a dual boot Android/Linux firmware, please refer to the Gemini Firmware to learn how to generate the scatter file.

Once you select the scatter file, the table should be populated as below:


Finally, change the Download Only drop down menu to Firmware Upgrade and click on the Download button. Connect your Gemini and restart it. . Once rebooted, the flash tool will detect the phone and it will update the OS with the selected firmware.

Notes on flashing firmwares

When switching between a standard Android to a dual boot Android/Linux firmware, you will need to use the Firmware Upgrade mode because you need to format the device. If you don't need to repartition the device, you can use the Download Only mode and flash a single partition without formatting. This is useful because you can update the Android system partition without deleting your data (which is stored in the user data partition), or you can update the boot.img and switching from an Android system to a rooted one or viceversa.

Linux dual boot notes

The dual boot mechanism works as follow:

  • Dual boot Android-Linux firmware
    • Press Esc (On) for around one second to turn ON the unit and boot into Android. You should release the Esc (On) button before the screen turns ON, otherwise the unit will boot into recovery mode (see below).
    • Press Esc (On) for around one second to turn ON the unit and at the same time press and hold the side button until the screen turns ON to boot into Linux. You should release the Esc (On) button before the screen turns ON, but you must keep the side button pressed until you see the turning ON. When the screen turns ON you can release the side button, and the unit will boot into Linux.
    • Press Esc (On) and keep pressing the button until the screen turns ON to boot in recovery mode. At this stage the recovery mode is disabled and you will see a droid image with a red triangle and a "No command" text.