You are not satisfied with the possibilities of the stock firmware.
Where can I find the firmware?
On the official website of the phone manufacturer.
On sites where developers post custom or official OS.
What should be done before installing the firmware?
Create a backup copy of user data and transfer it to another medium.
Insert SD card. An SD card is needed to write firmware to it.
Determine your smartphone model.
Fully charge your phone. If the battery runs out during boot, the device will no longer turn on.
Download archive with Firmware. Place it on the SD card.
Installing TWRP Recovery
Download the Official TWRP App from the Play Market. Download, install and launch the 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.
On the next screen, select 'TWRP FLASH' and give the application root rights.
On the main screen of the application, click 'Select Device', and select your phone model.
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.
After downloading the image file, 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 that you are ready to start the procedure - press 'OK' in the question window.
When the message 'Flash Completed Succsessfuly!' appears on the screen. Click the 'OK' button. The TWRP installation procedure is now complete.
Write the firmware to the SD card. Using a PC or laptop card reader.
Insert a memory card into the device.
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 'Reboot' and then click on the 'REBOOT RECOVERY' button.
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.
You can start flashing. Click the 'Install' button.
The file selection screen appears. At the very top is the 'Storage' button, select the location where the firmware file is located.
Select the location where the files were copied. Press the 'OK' button.
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 flashing the phone will begin, accompanied by the appearance of inscriptions in the log field and the movement of the progress bar.
After the firmware installation procedure is completed, the 'Successful' message appears on the screen.
Summary: Type: Smartphone; Smart Phone OS: Android; OS ver: Android 6.0 Marshmallow; SIM: Micro SIM, Dual SIM, Dual Standby; CPU: Mediatek MT6580Quad Core Cortex-A53; Processor Speed: 1.3 GHz; Storage: 8GB; RAM: 1GB; External Storage: microSD up to 128GB; Battery: Li-ion 5000 mAhNon-removable; Screen Size: 5 inches; Resolution: HD 294 PPI 1280 x 720 pixels; Main Camera: 8 MP; Front Camera: 5 MP; Features: WiFi , GPS , Bluetooth , Flash; Dimensions: 143 x 73 x 9.9 mm; ...
Comments, questions and answers on the flash firmware CloudFone Thrill Power