oppor7s system is Android 4.4.4. How can I upgrade it to Android 5.1 system?

How to upgrade your mobile phone

There are 2 upgrade methods for new version updates:

1. Online upgrade: You can use "Mobile Desktop--System Update" Check whether there is a new version pushed. If a new version is detected, you can click to download and install it. During the installation process, the phone will automatically shut down. Make sure the phone battery is above 40% before operating, otherwise it will prompt that it cannot operate.

2. Manual flashing:

① Back up data (contacts, text messages, etc.) through "Mobile Desktop--Cloud Service" or through "Tools-- "Backup and Restore" to operate;

② Download the firmware package of the mobile phone in the "Firmware Download Area" and move it and store it in the root directory of the mobile phone;

③ Double clear after the backup is completed : After shutting down, press and hold the power button + volume down button for about 10 seconds to enter OPPO recovery mode, select Chinese Simplified - Clear data and cache;

④Select to install the upgrade package, click on the stored firmware package, and confirm upgrade.

"Mobile Desktop--System Update" online upgrade operation failed:?

1. Mobile Phone Settings--Applications--All--System Update, clear the data and try the operation again ;

2. It may be caused by network instability. It is recommended to switch to other networks to try;

3. The phone has been rooted. After rooting, it will not be able to be upgraded normally. Please download the model Manually upgrade the firmware package.

Downloading the firmware package and manually flashing the phone failed:

1. The phone has backed up important data (text messages, contacts, etc.) (can be accessed through "Mobile Desktop - Cloud Service" or "Tools" --Backup and Restore" to operate);

2. Confirm that Dual Clear has been operated: After shutting down, press and hold the power button + volume down button for about 10 seconds to enter OPPO recovery mode, select Chinese Simplified - Clear Data and cache;

3. If manual flashing still fails after double clearing is confirmed, it is recommended that you bring the relevant warranty certificate to the customer service center for inspection and processing.