To close all background running apps on a ZTE Nubia Neo, follow these steps:
Hold down the Power button or Home button to bring up the device's menu. (The specific button may vary depending on your device's settings and Android version.)
Select the "Apps" or "Applications" option, which typically appears as a grid of installed apps or a series of app icons.
Locate the app you want to close and swipe it away from the screen or tap the "X" button in the corner of the app preview to close it.
Repeat step 3 for each app you want to close.
Unfortunately, there is no direct method to close all background apps simultaneously on a ZTE Nubia Neo, as each app must be closed individually. If you find that your device is slow or experiencing performance issues, consider closing apps that you haven't used in a while or that are known to consume a lot of system resources. Additionally, you can use third-party task manager apps or device cleaners to optimize your device's performance.