You are not satisfied with the functionality of the stock firmware.
Where can I find the firmware?
On the official website of the manufacturer.
On specialized services on which developers lay out custom or official OS.
What should be done before installing the firmware?
Back up your contacts and user data and transfer it to your computer.
Insert your SD card into your phone. It must have enough memory to fit the firmware.
Remember your smartphone model.
Fully charge your device's battery.
Download the archive with Firmware and place it on the SD card.
Installing TWRP Recovery
Install the Official TWRP App via the Play Market. And run this application.
When you start the application for the first time, you must agree to install a new firmware and all the risks associated with this, as well as agree to grant the application Superuser rights and click the 'OK' button.
In the next screen, select the item 'TWRP FLASH' and provide the application with root-rights.
On the main screen of the application, the 'Select Device' drop-down list is available, in which you need to find and select the device model for installing the recovery.
After selecting the phone, the application will redirect the user to a web page to download the modified recovery environment image file. Download the proposed *.img file.
When the file is loaded, return to the main screen of the Official TWRP App and press the 'Select a file to flash' button. Select the file downloaded in the previous step.
Now press the 'FLASH TO RECOVERY' button and confirm your choice, press 'OK'.
When the message 'Flash Completed Succsessfuly!' appears on the screen. Click the 'OK' button. The TWRP installation procedure is now complete.
Write the firmware and other necessary files to the SD card. Using a PC or laptop card reader, it will be much faster.
Insert a memory card into the device.
To reboot in recovery, it is convenient to use a special item in the Official TWRP App menu, accessible by pressing the button with three stripes in the upper left corner of the main screen of the application. We open the menu, select the 'Reboot' item, and then tap on the 'REBOOT RECOVERY' button. The phone will reboot into the recovery environment automatically.
Firmware via TWRP
Before flashing, it is recommended to clear the 'Cache' and 'Data' sections. This will delete all user data from the device, but avoid a wide range of software errors and other problems. You must press 'WIPE' on the main screen.
Everything is ready to start flashing. Press the 'Install' button.
The file selection screen is displayed. At the very top is the 'Storage' button, select the location where the firmware file is located.
Select the location where you copied the files. Press the 'OK' button.
Select the firmware file and click on it. A screen opens with a warning about possible negative consequences, you need to check the item 'Zip signature verification', which will avoid using damaged files during recording.
The procedure for writing files to the phone's memory will begin, accompanied by logging and filling in the progress bar.
The completion of the installation procedure is indicated by the inscription 'Successful'.
Summary: Type: Mobile; Battery: Li-Ion 2500 mAh; CPU: MediaTek MT6737, Quad Core, 1.25GHz, ARM Mali-T720 MP2; Smart Phone OS: Android 7.0; Dimensions: 145 x 71.7 x 8.5 mm; Formfactor: Bar; Keyboard: Screen; Sidekeys: Volume, Power; Softkeys: 3; Weight: 138 g; Color: Yes; Colors: 16M; Other: Capacitive Touchscreen, Multitouch; Pixel aspect ratio: 2.00; Resolution: 640x360; Display PPI: 294; Screen Size: 5; Type: IPS; Audio: AAC, AAC+, AMR, AWB, MP3, Vorbis, FLAC, APE, MIDI, WAV; Camera: 13MP, 4128x3096; Other: LED Flash, Autofocus, Continuous Shooting, Digital Zoom, Digital Image Stabilization, Geo-Tagging, Panorama, High Dynamic Range (HDR), Touch Focus, Face Detection, White ...
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