You want to update the firmware, as it does not suit you in terms of functionality.
Where can I find the firmware?
On the official website of the 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.
Determine your smartphone model.
Charge your phone fully. If the battery runs out during boot, the device will no longer turn on. It will be difficult to restore it.
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.
In the next screen, select the item 'TWRP FLASH' and provide the application with root-rights.
On the main screen of the application, click 'Select Device', and find your phone model.
After selecting the phone, the program will redirect the user to a web page to download the corresponding image file of the modified recovery environment. 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. 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 enter the menu accessible by pressing the button with three stripes in the upper left corner of the main screen of the application. 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.
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..
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.
When the procedure for installing the firmware is completed, the message 'Successful' appears on the screen.
Summary: OS: Android 4.2 Jelly Bean, upgradable to 4.4 KitKat; CPU Speed: 1.3 GHz; Primary display: LCD 4.7" 960 x 540 pixels 16M colors qHD, 234 ppi; Secondary display: No; RAM: 1 GB; Memory Card: MicroSD, Up to 32 GB; Primary camera: 8 MP 3264 x 2448 pixels LED flash; Secondary camera: 2 MP 1600 x 1200 pixels; Headphone: Yes 3.5mm; WI-FI: Yes 0; NFC: No; GPS: Yes A-GPS; Bluetooth: No; HDMI: No; Hotknot: No; USB: Yes; Infrared: No; Waterproof: No; Dustproof: No; Shock resistant: No; Sensors: Motion sensor, Proximity sensor; Capacity: 1800 mAh Li-Ion; Dimension: 134.5 x 67.7 x 8.07 mm; SIM: Mini-SIM, Dual-SIM; Colors: black; ...
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