Plenty of Android users report this: the connection was working fine, then it suddenly drops, and reopening the client shows the status has changed to "Not connected." This usually isn't a bug in the client — it's your phone's power-saving policy killing it in the background.

The Symptom: Why It Disconnects on Its Own

To improve battery life, Chinese phone manufacturers generally apply more aggressive background management to apps that "aren't visible in the foreground" — throttling power, pausing network access, or even killing the process outright. This is usually called "power-saving mode" or "background management." Because of how v2rayNG works, it needs to keep a local VPN connection and traffic-forwarding process running in the background at all times. Once the system flags it as an "inactive app," that background process can get force-cleared — which shows up as "it was working a minute ago, and now the icon shows disconnected."

This isn't really a flaw in v2rayNG or similar clients — it's a natural conflict between Chinese phones' background management policies and any app that needs to keep running in the background long-term. Messaging, navigation, and music apps run into the exact same background-clearing issue, and the fix is basically the same: explicitly tell the system this app needs to keep running in the background and shouldn't be restricted.

The Fix: Add the Client to Your Battery Whitelist

Menu names vary slightly by phone brand, but the general path is similar: find the "Battery/Power management" settings, switch v2rayNG from "Auto-manage/Smart power saving" to "No restrictions/Allow background activity," and make sure "Auto-start" permission is also allowed (on some devices, disabling auto-start means the app process disappears completely after a restart, and no whitelist setting can keep it running in the background). Here are the specific steps for common brands:

  • Xiaomi / Redmi (MIUI/HyperOS): Settings → App settings → App management → find v2rayNG → Battery saver → select "No restrictions"; also allow auto-start under "Autostart management."
  • Huawei / Honor (HarmonyOS/EMUI): Settings → Battery → App launch management → find v2rayNG → turn off "Manage automatically," then manually enable "Allow auto-launch, secondary launch, and run in background."
  • OPPO / vivo (ColorOS/OriginOS): Settings → Battery → App power management → find v2rayNG → allow "Background activity/High power usage."
  • Samsung (One UI): Settings → Battery → Background usage limits → make sure v2rayNG isn't in the "Sleeping apps" or "Deep sleeping apps" list.
  • OnePlus (OxygenOS/ColorOS): Settings → Battery → Battery optimization → find v2rayNG, select "Don't optimize," and keep it allowed under "Autostart management."

Why "Auto-Start" Matters Too

Many people only set up the battery whitelist and forget the auto-start permission. As a result, after a restart or a long lock-screen period, v2rayNG's background process gets cleared along with everything else — the client icon is still there, but it's no longer actually running until you open it again manually. Set up both "allow auto-start" and "battery whitelist" together to get a true set-it-once setup.

Settings May Look Slightly Different Across Manufacturers

After a system update, the menu names and levels listed above might shift slightly — for example, some devices rename "Battery saver" to "Power protection," or move the setting from Settings → Battery to Settings → App management → v2rayNG → Permissions. If you can't find the option using the paths above, try searching "battery optimization" or "auto-start" directly in your system settings — most devices support in-system search, which is faster than digging through menus manually.

A Few More Tips

After setting this up, keep an eye on the connection for a day or two, especially after long lock-screen periods or switching to memory-heavy apps (like games). If certain devices still disconnect after setup, try searching "auto-start" or "lock background" in system settings — some devices offer a quick toggle to lock an app from being cleared (for example, long-press the app icon in recent apps and select lock).

If it keeps disconnecting even after following the steps above, first rule out whether the subscription node itself is unstable — try switching to a different node. If the problem persists after switching, check the troubleshooting guide for other possible causes.

How to Confirm the Setup Actually Worked

Once you're done, do a quick real-world test: connect to a node, lock your phone for ten-plus minutes, then unlock it and check the client's status icon. If it still shows "Connected," the keep-alive setup is working. If it dropped, double-check that auto-start permission is also enabled — that's the most common thing people miss.

Do Tablets Need the Same Setup?

If you're using v2rayNG on an Android tablet, we'd recommend setting up the same battery whitelist described above — tablets generally run on the same underlying system as phones, so background management policies are basically the same. The setting is usually still near Settings → Battery; check the paths for your brand above, or search "battery optimization" in system settings if you can't find it.

Overall, keep-alive setup is a configure-once, benefit-long-term kind of task. The first setup might take a few minutes of digging through menus, but you shouldn't need to touch it again — unless you get a new phone or a major system update resets your battery settings to default, in which case just repeat the same steps.