Errors in the operation of the Android OS begin to appear.
Some installed applications do not open.
Some programs from the Play Market do not start.
The phone shuts down and restarts for no apparent reason.
The phone began to work slowly.
You want to update your firmware.
Where can I find the firmware?
On the official website of your phone manufacturer.
On sites where third-party developers and phone manufacturers 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 your SD card into your phone. It must have enough memory to fit the firmware.
Remember your smartphone model.
Fully charge your device. If the battery runs out during the firmware, the device will no longer turn on.
Find and download the archive with Firmware. 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 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.
After moving to the next screen, you need to select the 'TWRP FLASH' item and give the application root rights.
On the main screen of the application, select 'Select Device', and find your phone model.
After selecting a device, the application will direct the user to a web page to download the appropriate modified recovery environment image file. Download the suggested *.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'.
When the message 'Flash Completed Succsessfuly!' appears on the screen. Click the 'OK' button. The TWRP installation procedure is now complete.
Copy the firmware and other necessary files to the SD card.
Insert a 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. We open the menu, 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.
Now you can start flashing. Press the 'Install' button.
On the file selection screen, at the very top there is a 'Storage' button for selecting an SD card.
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 writing files to the phone's memory will begin, accompanied by logging and filling in the progress bar.
The completion of the firmware installation procedure is indicated by the inscription 'Successful'.
Summary: GSM frequencies: 850 900 1800 1900; Standard UMTS: 900 2100; Standard LTE: no; Type: Touch; Dimensions (W x H x D): 129.80 x 68.00 x 10.95 mm; Weight: 143.00 g; Main display: Color / TFT16M colors480 x 800 px (4.30") 217 ppi; Display protection: no; Talk time (max.): 2G: 960 min. (16.0 h)3G: 510 min. (8.5 h); Stand-by (max.): 2G: 400 h (16.7 days)3G: 350 h (14.6 days); Playback time (max.): Audio: 30 h; Standard battery: Li-Ion 1800 mAh; Quick battery charging: no; Internal memory: 4 GB; RAM memory: 1 GB; Memory cards: yes, microSD, microSDHC (up to 32 GB); Operating system: Android 4.0 Ice Cream Sandwich; Processor: MediaTek MT6577; Processor clock: 1.0 ...
Comments, questions and answers on the flash firmware Alcatel OT-997D