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 shuts down and restarts for no apparent reason.
The phone is slow.
You are not satisfied with the functionality of the stock firmware.
Where can I find the firmware?
On the website of your phone manufacturer.
On sites 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 another medium.
Insert an SD card into your phone to write the firmware to it.
Remember 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 to your phone from the Play Market. And install this app.
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, the 'Select Device' drop-down list is available, in which you need to find and select the device model for installing the recovery.
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, go 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.
After adding the image file to the program, click the 'FLASH TO RECOVERY' button and confirm your choice, click 'OK'.
After the burn process is complete, the message 'Flash Completed Succsessfuly!' appears. Click 'OK'. The TWRP installation procedure can be considered complete..
Copy the firmware and other necessary files to the SD card.
Insert a memory card into the phone.
To reboot in recovery, it is convenient 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 tap 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. You will delete all user data from the phone, this will avoid software errors and other problems.
Everything is ready to 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 the files were copied.
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 phone's memory will begin, this is accompanied by the appearance of inscriptions in the log field and the movement of the progress bar.
The completion of the installation procedure is indicated by the inscription 'Successful'.