Errors constantly appear in the Android operating system.
Some applications do not open, reinstalling which does not lead to a positive result.
Many programs from the Play Market do not start.
The phone turns off for no apparent reason.
The phone began to slow down a lot.
You are not satisfied with the functionality of the stock (official) firmware.
Where can I find the firmware?
On the website of your phone 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 an SD card into your phone to write the firmware to it.
Determine your smartphone model.
Fully charge your device.
Download the archive with Firmware and place it on the SD card.
Installing TWRP Recovery
Download the Official TWRP App to your phone from the Play Market. And install this app.
When you start the application for the first time, you need to give consent to future manipulations, as well as to give consent to granting the application Superuser rights and click 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, click on the 'Select Device' drop-down list, and select 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.
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.
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 can be considered 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 SD 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. Open the menu and select the 'Reboot' item, and then click on the 'REBOOT RECOVERY' button.
Firmware via TWRP
Before flashing, you need to clear the 'Cache' and 'Data' sections, press 'WIPE' on the main screen. You will delete all user data from the phone, this will avoid software errors and other problems.
Now you can start flashing. Press 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, 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 writing files to the phone's memory will begin, this is accompanied by the appearance of inscriptions in the log field and the movement of the progress bar.
After completing the installation procedure, a 'Successful' message appears on the screen.