You are not satisfied with the functionality of the stock firmware.
Where can I find the firmware?
On the phone manufacturer's website.
On specialized services 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 SD card. An SD card is needed to write firmware to it.
Remember your smartphone model.
Fully charge your phone. If the battery runs out during boot, the device will no longer turn on.
Find and download the archive with Firmware.
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 agree to install the firmware, as well as agree to grant the application Superuser rights and click the 'OK' button.
Going to the next screen, select the item 'TWRP FLASH' and provide the application with 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 device, the program redirects the user to a web page to download the corresponding image file of the modified recovery environment. Download the suggested *.img file.
When the file is loaded, you need to 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 is now complete.
Copy the required files to the memory card. Using a PC or laptop card reader.
Insert a SD 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 delete all user data from the phone, this will avoid many problems. press 'WIPE' on the home screen.
Everything is ready to 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 storage to which the files were copied.
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 flashing the phone will begin, 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'.
Summary: Type: Mobile; Battery: Li-Ion 2200 mAh; CPU: MediaTek MT6589, Quad Core 1.2GHz, ARM Cortex A7, PowerVR SGX544; Smart Phone OS: Android 5.0.1; Dimensions: 137.9 x 70 x 9.65 mm; Formfactor: Bar; Keyboard: Screen; Sidekeys: Volume; Color: Yes; Colors: 16M; Other: Capacitive Touchscreen, Multitouch; Pixel aspect ratio: 2.00; Resolution: 360x640; Display PPI: 306; Screen Size: 4.8; Type: Super AMOLED; Audio: AAC, AAC+, AMR, AWB, MP3, Vorbis, FLAC, APE, MIDI, WAV; Camera: 13MP, 4128x3096; Other: LED Flash, Autofocus, Continuous Shooting, Digital Zoom, Digital Image Stabilization, Geo-Tagging, Panorama, High Dynamic Range (HDR), Touch Focus, Face Detection, White Balance, ISO, ...
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