Errors constantly appear in the Android operating system.
Some installed applications do not open.
Many applications from the Play Market do not start.
The phone turns off for no apparent reason.
The phone began to work slowly.
You are not satisfied with the functionality of the stock (official) firmware.
Where can I find the firmware?
On the official Internet resource of the phone manufacturer.
On Internet resources where users post 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.
Determine your smartphone model.
Fully charge your phone battery.
Download archive with Firmware.
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.
After moving to the next screen, select the 'TWRP FLASH' item and provide the application with root rights.
On the main screen of the application, click on the 'Select Device' drop-down list, and select 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, 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.
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.
Copy the necessary files to the SD memory 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. Open the menu and select the 'Reboot' item, and then click on the 'REBOOT RECOVERY' button.
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. Press the 'Install' button.
The file selection screen appears. 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, 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.
After completing the installation procedure, a 'Successful' message appears on the screen.