You want to update the firmware, as it does not suit you in terms of functionality.
Where can I find the firmware?
On the official website of the manufacturer.
On sites where third-party developers post custom operating systems.
What should be done before installing the firmware?
Create a backup copy of user data, contacts and photos and transfer it to your computer.
Insert your SD card into your phone. An SD card is needed to write firmware to it.
Determine your smartphone model.
Fully charge your device's battery.
Download archive with Firmware. Place it on the SD card.
Installing TWRP Recovery
Download and install the Official TWRP App from the Play Market.
When you start the application for the first time, you must agree to install the firmware, 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, click 'Select Device', and find your phone model.
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 download is finished, you need to return to the main screen of the Official TWRP App and click on the 'Select a file to flash' button. Select the file downloaded in the previous step.
Press the 'FLASH TO RECOVERY' button and confirm your choice, press 'OK'.
When the message 'Flash Completed Succsessfuly!' appears. Click 'OK'. The TWRP installation procedure is now complete.
Transfer the necessary files to the SD memory card. Using a PC or laptop card reader, it will be much faster.
Insert a memory card into your phone.
To reboot into recovery, you need to enter the menu accessible by pressing the button with three stripes in the upper left corner of the main screen of the application. Select the 'Reboot' item, and then click on the 'REBOOT RECOVERY' button. The phone will reboot into the recovery environment automatically..
Firmware via TWRP
Before flashing, you need to delete all user data from the phone, this will avoid errors in the software, as well as other problems. Press 'WIPE' on the home screen.
You can start flashing. Click 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 storage to which the files were copied.
Find the file we need 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 corrupted files when writing to the phone's memory sections.
The procedure for flashing the phone will begin, this is accompanied by the appearance of inscriptions in the log field and the movement of the progress bar.
When the procedure for installing the firmware is completed, the message 'Successful' appears on the screen.
Summary: OS: Android v9.0 (Pie); Screen Resolution: 1080 x 2340 Pixels; Screen type: IPS LCD; Pixel density: 403 ppi; Touch screen: Yes, Capacitive Touchscreen, Multi-touch; Internal memory: 64 GB; Front camera: 16 MP; Front camera: 16MP, HDR, 1080p; Main camera: 24 MP 8 MP 5 MP; Resolution: 24 MP, f/1.8, 1/2.8", 1.12Вµm, Dual Pixel PDAF, 8 MP, f/2.4, 13mm , 5 MP, f/2.4, depth sensor; Camera setup: Single; Flash: Yes, LED Flash; Autofocus: Yes; Shooting modes: Continuos Shooting, High Dynamic Range mode (HDR); Video recording: Yes; Settings: Exposure compensation, ISO control; Camera features: Digital Zoom, Auto Flash, Face detection, Touch to focus; Sim 1: 4G Bands: TD-LTE 2600(band 38) / 2300 ...
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