Why Does My Huawei or Honor Phone Stop the Camera App With the Screen Off? App Launch, Protected Apps and PowerGenie

You set up an old Huawei or Honor phone as a camera. It is on the charger, the screen is off, and the camera app is recording. When you come back, the recording stopped long ago. No error. The app is closed, or it opens fresh as if it never ran.

On these phones that is usually not a broken phone and not a broken app. It is the phone's own power management, which closes apps you are not looking at. A camera with the screen off is exactly that kind of app.

This guide shows the settings that cause it on Huawei's EMUI software (which older Honor phones also use), where to find them, and how to test your phone in ten minutes. It is written for a simple setup: one spare Android phone, no cloud account, no subscription, often no SIM card and only home or shop Wi-Fi.

Why does my Huawei or Honor phone stop the camera app when the screen is off?

Because Huawei adds several of its own background limits on top of normal Android, and some of them are on by default.

The volunteer site Don't Kill My App tracks how phone brands treat background apps and gives each brand a problem score out of 5. At the time of writing, Huawei scores 5, the highest score on the list. Plain Android (AOSP) scores 0.

Its Huawei page puts it plainly:

"On default settings, background processing simply does not work right and apps working in background will break."

It also says there are "no APIs and no documentation" for these extensions. That is the important part.

An app can ask Android for permission to keep running with the screen off. That is what a foreground service is, and it is why a screen-off camera app shows a notification while it records. But Huawei's extra switches are not something an app can flip for you. Only the person holding the phone can.

One more thing the page says, which explains why fixing this feels like whack-a-mole: "Huawei phones usually have multiple powersaving mechanisms." Fixing one switch is often not enough. Work through the whole list.

Which phones this is for

Don't Kill My App's Huawei page names models such as the Huawei P20, P20 Lite, Mate 10, P9 Plus, Mate 9 Pro and the Honor 9 Lite, across EMUI versions 4 to 10. Phones from that era are exactly the kind that end up in a drawer and then become a camera.

Newer Honor phones run Honor's own software (MagicOS). The page does not cover it, so menus on those phones may differ. The same ideas apply: look for app launch, battery optimization, and power-saving settings, and run the test at the end.

The six settings that stop a screen-off camera on Huawei and Honor

Menu names change between EMUI versions and models. If a step does not match your phone, use the search box at the top of Settings and type the bold words. You will not have every one of these on every phone. Do the ones you find.

1. App launch: Manage manually, all switches on

This is the main one on EMUI 8, 9 and 10 phones (the page lists the P20, P20 Lite and Mate 10).

• Go to Settings → Battery → App launch.
• Find your camera app and turn off "Manage all automatically" for it.
• In the box that opens, turn on every switch. Don't Kill My App writes "Make sure to ENABLE! all toggles."

On the Honor 9 Lite and Mate 9 Pro the page gives the same idea under a shorter name: Settings → Battery → Launch, set the app to Manage manually, and make sure everything is turned on.

2. Battery optimization: Don't allow

This is the standard Android battery rule, in Huawei's own wording.

• EMUI 9 and newer: open Settings, search for Battery optimization. Tap the small triangle next to Don't allow, choose All apps, find your camera app, and select Don't allow.
• EMUI 5 and 8: search for Ignore battery optimization. Tap the triangle next to Allow, choose All apps, find your camera app, and select Allow.
• Huawei P9 Plus: Settings → Apps → Settings → Special access → Ignore battery optimisation, and allow your camera app.

The words are opposite on different versions ("Don't allow" optimization vs "Allow" to ignore it). Both mean the same thing: do not optimize the camera app.

3. Protected apps and "Keep running after screen off" (EMUI 5 and 6)

Older EMUI phones have a list of Protected apps.

• Settings → Advanced Settings → Battery manager → Protected apps: set your camera app as Protected.
• Settings → Apps → [your camera app] → Battery: turn off Power-intensive prompt and turn on Keep running after screen off.

That second switch has the clearest name of anything in this guide. If you see it, turn it on.

4. Startup manager

The page calls it "a new kid on the block", a list that stops apps from running automatically after the phone starts up.

• Settings → All → Startup manager, and allow your camera app.

This matters after a power cut. If the phone restarts and the camera app is not allowed here, it may not come back by itself.

5. Smart tune-up in System Manager

Huawei phones come with a pre-installed app called System Manager. Don't Kill My App says it has a "smart" feature that can close apps.

• Open System Manager, tap the cog (settings) icon, and turn off Smart tune-up.

Also tell everyone in the house or shop not to tap the big "optimize" or "clean" button on the camera phone.

6. Power plan and power saving modes

These are whole-phone modes. When they are on, they tighten the rules for every app at once, including the one you just allowed.

• Check Settings → Battery and make sure any power saving mode is off, and is not set to turn on by itself at low battery.
• On EMUI 6 and some EMUI 5 phones, Don't Kill My App also suggests Battery manager → Power plan → Performance. That changes the whole phone and can make it warmer. Do steps 1 to 5 first, run the test below, and only change the power plan if the test still fails.

A camera phone lives on the charger, so it does not need power saving. If the battery still drops while plugged in, the charger is the problem, not the settings. We explained that in Why Does My Phone Security Camera's Battery Drop Even Though It Is Plugged In?.

The hard cases: PowerGenie and EMUI 4

Two things on Huawei phones cannot be fixed with normal settings. Know about them before you pick a phone for the job.

PowerGenie (some EMUI 9 and newer phones)

Don't Kill My App says some EMUI 9+ phones include a task killer called PowerGenie that "kills all apps that are not on its whitelist", and that "you cannot add custom apps" to that list. The site also says reviews are mixed: PowerGenie is on some EMUI 9+ phones and not on others.

Their fix is advanced. It needs a computer, a USB cable, USB debugging, and these ADB commands:

adb shell pm uninstall -k --user 0 com.huawei.powergenie
adb shell pm uninstall -k --user 0 com.huawei.android.hwaps

Our advice: do not start here. Do the six settings, then run the test. Only if the camera still stops, and you are comfortable with ADB, consider this step. It removes a system app for the main user. A factory reset brings it back. The site also mentions a possible simpler route, disabling PowerGenie under Settings → Apps, but says that is not confirmed and would need redoing after every restart.

EMUI 4 (Android 6 era phones)

Don't Kill My App says that on EMUI 4 "there is no way out" for users. A service called HwPFWService force-stops apps that hold a wakelock for more than 60 minutes. The only workaround the page knows is in the app's own code, not in your settings.

If your spare phone is that old, a one-hour camera test will tell you quickly. If it fails at about the one-hour mark every time, choose a different phone for the camera.

Does this work without internet?

Yes. None of the settings above need internet, a SIM card, or an account. They are local switches on the phone.

That matters for a common setup in shops and homes: the camera phone has no SIM and only joins the local Wi-Fi, or no Wi-Fi at all. Recording to the phone's own storage does not need internet. A live view inside the same Wi-Fi network does not need internet either, as long as the router is on. Streaming to YouTube Live is different: that one needs a working internet connection.

Why a phone with 2 GB or 3 GB of RAM can still stop

Many spare Huawei and Honor phones are older "Lite" or budget models with little memory. On those phones two different things can stop your camera:

1. Huawei's power rules (this guide). These are settings. You can change most of them.
2. Android's low-memory killer. When memory is full, Android itself closes apps, starting with the least important. A foreground service ranks high, but it is not untouchable.

The settings here fix the first one. For the second: use the phone for the camera only, remove apps you do not need, and do not run games or social apps next to the camera. We explained how Android picks what to stop in A Foreground Service Is Not Immortal: What Android's Low Memory Killer Does to a 24/7 Camera on a 2 GB Phone.

The 10-minute test (and the 70-minute test)

Changing settings is not proof. Test the real phone with the real app.

1. Make the changes above. Restart the phone once.
2. Open the camera app, start recording, and turn the screen off.
3. Note the time. Put the phone on the charger. Do not touch it.
4. Wait at least 10 minutes. On Huawei, wait at least 70 minutes for a second check, because the EMUI 4 limit described above acts after 60 minutes. A full night is best.
5. If your app has a live view over Wi-Fi, open it from a second phone or laptop while you wait. Is the picture still moving?
6. Unlock the camera phone and look at the recordings. Do the files continue past the time you noted, with no long gap?
7. If there is a gap, note roughly when it started. A gap soon after the screen went off usually means a battery or app launch setting was missed. A gap at almost exactly one hour points to the EMUI 4 limit, or to a similar timer. A gap that starts after someone used the phone points to a cleaner or Smart tune-up.

Run the test again after every EMUI update. Updates can add new power features, move menus, or reset switches.

Quick checklist for a Huawei or Honor camera phone

• [ ] App launch: camera app set to Manage manually, all switches on
• [ ] Battery optimization: camera app not optimized
• [ ] Older EMUI: camera app Protected, Keep running after screen off on
• [ ] Startup manager: camera app allowed
• [ ] Smart tune-up off, and nobody taps "optimize" on the camera phone
• [ ] Power saving modes off, and not set to turn on automatically
• [ ] 10-minute test, then a 70-minute test, then an overnight test
• [ ] Only if it still fails: power plan, then (advanced) PowerGenie
• [ ] Re-test after every system update

If you have a different brand

• OPPO, realme or vivo: see Why Does My OPPO, realme or vivo Phone Stop the Camera App With the Screen Off?
• Redmi, POCO or Xiaomi: see Why Does My Redmi, POCO or Xiaomi Phone Stop the Camera App With the Screen Off?
• Tecno, Infinix or itel: see Why Does My Tecno, Infinix or itel Phone Stop the Camera App With the Screen Off?
• Samsung: the night-time trap there is a scheduled automatic restart. See Why Does My Samsung Phone Camera Stop Recording at Night?
• Developers who want the Android side (Doze, foreground services, and why vendor layers sit on top) can read Why Does My Android Camera Stop Recording When the Screen Turns Off?

New to this? Start with Turn an old Android phone into a screen-off security camera (no cloud, LAN-only), then come back to this checklist before you leave the phone alone.

Sources

• Don't Kill My App — Huawei (page dated 9 June 2026; score, quotes, App launch, Battery optimization, Protected apps, Keep running after screen off, Startup manager, Smart tune-up, Power plan, PowerGenie and ADB commands, EMUI 4 HwPFWService 60-minute limit, model names). Score read from the site's vendor list on 14 November 2026.

Don't Kill My App is a volunteer project, not official Huawei or Honor documentation. Menus differ by model and version, and the page itself says reports are mixed. That is exactly why the test matters more than the menu.

Background Camera RemoteStream turns an Android phone into a screen-off camera: it records with the screen off and keeps recordings on the phone, with no cloud account needed. Its Pro tier adds a live browser view over your own Wi-Fi and YouTube Live streaming; check the Play listing for what is free and what is Pro.

• Google Play: https://play.google.com/store/apps/details?id=com.superfunicular.digicam
• Website: https://superfunicular.com