For Android users who notice excessive standby drain after enabling v2rayNG, lose the connection when the screen locks, or want to limit which apps use the proxy. First distinguish data-related battery use from background reconnects, then adjust battery restrictions and per-app proxy settings as needed. Change one setting at a time and compare results over the same test duration.
Identify what's draining the battery
v2rayNG uses Android's VPN service interface to receive app traffic, then relies on the Xray core for routing and outbound connections. The VPN icon in the status bar means the service is active; it doesn't mean the phone is constantly transferring data at high speed. Battery use depends on factors such as data volume, encryption, mobile signal strength, connection retries, and apps making their own background requests.
For example, a video app caching content in the background, a photo app uploading images, or a sync app repeatedly fetching data can keep the proxy busy. How Android attributes VPN traffic in battery stats also varies by version and device manufacturer. So seeing v2rayNG at the top of the list doesn't mean the core itself used all that battery.
- Battery drains quickly while the screen is on: Check video playback, downloads, and screen brightness first. Compare power use with the same content on the same network instead of relying on the app ranking alone.
- High data use continues with the screen off: Check sync, updates, and media caching; the proxy may simply be carrying that traffic.
- Disconnects with the screen off and reconnects when it wakes: Check background restrictions before changing protocols.
- Little data use but frequent overheating: Look for repeated errors and retries, or network switching in areas with weak signal.
Track battery use under comparable conditions
Open Android Settings → Battery → Battery usage, then find v2rayNG and check the reporting period. Some systems show its share of total battery use during that period, not the percentage points lost from the battery's full capacity. An app accounting for 20% doesn't mean the battery dropped by 20 percentage points. Record the battery level at both the start and end of each test.
- Note the Android version, the version shown on v2rayNG's About page, the network type, and the node in use. Don't update the client between test runs.
- Start on a stable Wi-Fi network. Pause system updates, downloads, and video playback, then let the phone cool to its usual standby temperature.
- Run a 60-minute screen-off baseline: if it's safe to pause the proxy temporarily, disconnect v2rayNG and record the battery change.
- Reconnect to the same node, keep other conditions as similar as possible, and run another 60-minute screen-off test. Note any disconnects and background data use.
- Then change just one setting—for example, route only your browser through the proxy—and repeat the test. If the difference is unclear after a short test, extend it to 2–3 hours.
| Test condition | Duration | What to record |
|---|---|---|
| Baseline with proxy off | 60 minutes | Start and end battery levels, signal, background tasks |
| Current settings enabled | 60 minutes | Start and end battery levels, data use, disconnect times |
| Fewer apps routed through the proxy | 60 minutes | Start and end battery levels, app behavior, error count |
For example, if the battery goes from 80% to 77%, that's a drop of 3 percentage points. This illustrates how to record results; it's not a measurement from your phone or a benchmark for normal battery use. Battery levels are rounded, so a one-point difference in a single test doesn't prove an improvement. Repeat the test twice under similar conditions.
Decide whether to keep a change: test, then compare
Keep a change only if the connection remains usable, test conditions are comparable, and repeated results point in the same direction. If battery use drops because all requests have stopped working, fix connectivity first—being offline isn't an optimization.
Adjust battery optimization based on disconnects
Excluding an app from battery optimization reduces background restrictions; it doesn't reduce the amount of work the proxy does. If the proxy is already stable, setting it to Unrestricted may not save battery. Check this setting when the service stops after the screen locks. Even with background activity allowed, Android can't guarantee a network connection will stay alive indefinitely.
- Open the app details: Long-press the v2rayNG icon, select App info, then open Battery or App battery management. Menu names vary by Android version and manufacturer.
- Allow necessary background activity: If the options are Unrestricted, Optimized, and Restricted, make sure Restricted isn't selected. If the connection drops when the screen locks, try Unrestricted.
- Check the battery optimization list: Some systems put this under Settings → Apps → Special app access → Battery optimization. Switch to all apps, find v2rayNG, and select Don't optimize if needed.
- Check for manufacturer-specific restrictions: If App info includes settings such as Auto-start or Allow background activity, enable them if you need a persistent connection. Locking the app in Recents is a manufacturer-specific feature and doesn't replace battery permissions.
- Reconnect and verify: Return to v2rayNG and start the connection. Leave the screen off for 30 minutes, then unlock the phone and check that the service is still running and websites load normally.
If you only use the proxy during your commute, stop the service with the connection button on v2rayNG's main screen when you're done instead of relying on Android to kill the process. If Always-on VPN is enabled, check that system setting first to prevent the service from being started again. Keeping the VPN connected or connecting only when needed is a usage choice—there's no one-size-fits-all answer.
Route fewer apps through the proxy
In v2rayNG, open the sidebar and go to Settings → Per-app proxy. Enable per-app proxy, then check whether Bypass mode is on. Menu locations and labels can vary by version, so follow the instructions shown in the app. Typically, with Bypass mode off, selected apps use the VPN; with it on, selected apps bypass the VPN.
| Mode | What selecting an app does | Best for |
|---|---|---|
| Bypass mode off | Selected apps use the VPN | Only a few apps need the proxy |
| Bypass mode on | Selected apps bypass the VPN | Most apps need the proxy, with a few exceptions |
| Per-app proxy off | App selection list isn't applied | First rule out access issues caused by the app list |
If only your browser needs the proxy, turn off Bypass mode and select that browser. Save, then stop and restart the connection so the VPN picks up the updated app list. Test the browser and confirm other apps still connect normally; the key icon alone doesn't confirm the settings are working.
- Per-app proxy and traffic routing aren't the same thing: Apps included in the VPN still go through Xray routing rules and may connect directly or use a proxy outbound. Excluded apps generally don't go through those routing rules.
- Excluding an app doesn't stop it from using battery: Background video caching still uses network data and power when it bypasses the VPN. To reduce total data use, change that app's download and sync settings.
- Watch for app handoffs: A sign-in flow may switch from your browser to another app. If the two apps use different network paths, authentication or access may behave differently. Test the related apps together.
- Review the list after installing apps: In selected-app-only mode, newly installed apps usually aren't added automatically. Whether system apps appear also depends on the list's filter settings.
Trade-off: a shorter list is easier to verify
If only a few apps need the proxy, start with Only selected apps. Test sign-in, messaging, and downloads each time you add an app. Don't exclude a large number of system components at once, or you may mistake a broken feature for a node problem.
Use logs to tell retries from background shutdowns
Open Logs from the v2rayNG sidebar and compare entries with the time of a disconnect. The examples below are possible log snippets; prefixes, addresses, and wording vary by core and by the stage where a failure occurs. An isolated message doesn't indicate abnormal battery use. Repeated errors that coincide with background requests, signal changes, or overheating are more useful clues.
Error: i/o timeout
Cause: A network read or write timed out. The node may be unreachable, the connection unstable, or the destination slow to respond.
What to do: Retry the same request on stable Wi-Fi, then compare it with a known-working node. Avoid repeatedly testing every node, which adds extra traffic.
Error: network is unreachable
Cause: No usable network route was available at the time. This often happens during a network switch or when there's no route for a particular address family.
What to do: Confirm the phone itself can access the internet, then reconnect on a single network. If the error occurs only on a particular network, check its addressing and routing conditions.
Error: connection refused
Cause: The destination port refused the connection. The service may not be listening, the node configuration may be outdated, or the destination service may have rejected the request.
What to do: Use the destination shown in the log to distinguish a node connection from a website connection, then check the relevant address and port. Update the subscription only if the node configuration has actually changed.
If the logs stop completely after the screen turns off and startup entries return only after unlocking, investigate background restrictions, app process state, and possible crashes together. An empty log alone doesn't prove Android killed the app. If the service is still running but errors keep appearing, focus on the network or configuration instead of adding more background permissions.
- Keep only the timestamps and error snippets you need for diagnosis, and avoid leaving verbose logging enabled. Writing logs also adds work.
- Don't run live connection tests continuously just to keep the connection alive. Speed tests generate real traffic and should only be used when you need to compare connectivity.
- Before sharing logs, hide subscription URLs, credentials, and personal destinations. Troubleshooting doesn't require publishing your full configuration.
Common settings questions
Battery use increased after I excluded v2rayNG from optimization. Should I undo it?
Check whether background data use increased first. Sync tasks that were previously paused may now run continuously, so the extra drain may not be caused by the proxy itself. If you don't need a persistent connection, stop the service and set Settings → App info → Battery back to Optimized. Then compare with the same 60-minute test.
Other apps stopped working after I set the proxy to browser-only. What should I do?
Check whether Block connections without VPN is enabled in Android's VPN settings, then make sure Bypass mode isn't set the wrong way around. Note your current settings, temporarily turn off per-app proxy, and reconnect to isolate the issue. Restore the app list as needed. If changing network protection settings, be clear about which apps will connect directly afterward.
The notification is always visible. Does that mean v2rayNG is always using battery?
The persistent notification indicates that the foreground service is running; it doesn't show data volume or processor load. Check battery usage and app data statistics for the same period. Don't disable notifications just to hide the icon—you'll lose a useful way to monitor the service.
The phone heats up much more on mobile data. Should I switch clients?
Test somewhere with a stable signal, and avoid downloading and charging at the same time. Weak signal, frequent network changes, and high data use can all increase power consumption from wireless communication. Keep the client and node the same, compare Wi-Fi with mobile data, and determine whether the network or configuration is responsible before deciding what to change.
The connection drops every time I lock the screen. Should I turn off every battery-saving feature?
No. First adjust only v2rayNG's battery restrictions and the manufacturer's background permissions, then test with the screen locked for 30 minutes. If the problem persists, check the logs and system battery-saver mode. Keep restrictions on for other apps instead of allowing background activity across the entire phone for one service.