Some applications do not open, reinstalling which does not lead to a positive result.
Some applications from the Play Market do not start.
The phone restarts or shuts down for no reason.
The phone is slow.
The OS does not match the system requirements of the smartphone.
Where can I find the firmware?
On the website of your phone manufacturer.
On certain sites where developers post custom or official OS.
What should be done before installing the firmware?
Create a backup copy of user data and transfer it to another medium.
Insert your SD card into your phone. It must have enough memory to fit the firmware.
Find information about your smartphone model.
Fully charge your device.
Find and download the archive with Firmware. And place it on the SD card.
Installing TWRP Recovery
Download the Official TWRP App from the Play Market. Download, install and launch the application..
When you start the application for the first time, you must consent to future manipulations, as well as consent to granting the application Superuser rights. Check the checkboxes and press the 'OK' button.
On 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 phone, the application will direct the user to a web page to download the modified recovery environment image file. Download the proposed *.img file.
After downloading the image file, return to the main screen of the Official TWRP App and press the 'Select a file to flash' button. Then we tell the program the path where the file loaded in the previous step is located.
Press the 'FLASH TO RECOVERY' button and confirm that you are ready to start the procedure - press 'OK' in the question window.
After the burn process is complete, the message 'Flash Completed Succsessfuly!' appears. Click 'OK'. The TWRP installation procedure can be considered complete..
Transfer the necessary files to the SD card. Using a PC or laptop card reader.
Insert a memory card into the device.
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, you need to clear the 'Cache' and 'Data' sections, press 'WIPE' on the main screen. This will delete all user data from the device, but avoid a wide range of software errors and other problems.
Now you can start flashing. Click the 'Install' button.
The file selection screen is displayed. At the very top is the 'Storage' button, which allows you to switch between types of memory.
Select the location where you copied the files. Press the OK button.
Find the file we need 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 device's memory will begin, accompanied by the appearance of inscriptions in the log field and the completion of the progress bar.
The completion of the firmware installation procedure is indicated by the inscription 'Successful'.
Summary: OS: Android 8.1 Oreo; CPU: Quad-core 1.3 GHz Cortex-A7; GPU: Mali-400; Type: IPS LCD capacitive touchscreen, 16M colors; Screen Size: 5.0 inches, 68.9 cm 2 (~65.4% screen-to-body ratio); Resolution: 480 x 854 pixels, 16:9 ratio (~196 ppi density); Card slot: microSDXC; Internal: 32GB 1GB RAM; Single camera: 5 MP; Features: LED flash; Video: 720p@30fps; Single camera: 5 MP; Video: 720p@30fps; Loudspeaker: Yes; 3.5mm jack: Yes; Sensors: Accelerometer; Battery: Li-Po 2000 mAh battery; Dimensions: 144 x 73.1 x 10.3 mm (5.67 x 2.88 x 0.41 in); Weight: 146 g (5.15 oz); SIM: Dual SIM (Nano-SIM, dual stand-by); ...
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