The OS does not match the system requirements of the smartphone.
Where can I find the firmware?
On the official website of your phone manufacturer.
On specialized resources where users post custom or official OS.
What should be done before installing the firmware?
Back up your phone's user data.
Insert an SD card into the gadget. It must have enough memory for the firmware.
Find information about your smartphone model.
Fully charge your device. If the battery runs out during the firmware, the device will no longer turn on.
Find and download the archive with Firmware. Place it on the SD card.
Installing TWRP Recovery
Download the Official TWRP App from the Play Market. And install it.
At the first start, you need to give consent to future manipulations, as well as consent to granting the Superuser rights to the application. Check the checkboxes and press the 'OK' button.
After moving to the next screen, you need to select the 'TWRP FLASH' item and give the application root rights.
On the main screen of the application, select 'Select Device', and find your phone model.
After selecting a device, the application will direct the user to a web page to download the appropriate modified recovery environment image file. Download the suggested *.img file.
After downloading the image file, go 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.
Click the 'FLASH TO RECOVERY' button and confirm your choice, click 'OK' in the question window.
The recording process is very fast, and upon completion, the message 'Flash Completed Succsessfuly!' appears. Click 'OK'. The TWRP installation procedure can be considered complete.
Copy the required files to the SD card. Using a PC or laptop card reader, it will be much faster.
Insert a memory card into the phone.
To reboot into recovery, you need 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 click 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.
Now you can start flashing. Click the 'Install' button.
On the file selection screen, at the very top there is a 'Storage' button for selecting an SD card.
Select the location where you copied the files..
Select the firmware file and click on it. A screen opens with a warning about possible negative consequences, as well as the item 'Zip signature verification'. This item should be checked by placing a cross in the check-box, which will avoid using damaged files when writing to the phone's memory sections.
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 firmware installation procedure is indicated by the inscription 'Successful'.
Summary: Colors: Black; Dimensions: 86 x 169 x 16 mm; Weight: 307 g, 0.68 lbs, 10.83 oz; Body materials: Plastic, Rubber; Type: IPS; Display Colors: 24 bit, 16777216 colors; Size: 5.5 in, 139.7 mm, 13.97 cm; Screen-to-body ratio: 57.56%; Resolution: 1080 x 1920 pixels; Pixel Density: 401 ppi, 157 ppcm; Protection: Corning Gorilla Glass 4; Display features: Multi-touch, Capacitive, Scratch resistant; Primary: 4160 x 3120 pixels, 12.98 MP; Video Recording: 1280 x 720 pixels, 0.92 MP at 30 fps; Secondary: 2560 x 1920 pixels, 4.92 MP; Camera Features: Continuous shooting, Autofocus, Geotagging, Digital zoom, HDR, Panorama, Face detection, Touch focus, ISO settings, White balance settings, ...
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