How Secure Is the App Locker For Android?

If you do a quick search of the phrase “app lock” in Google Play Store, you will find plenty of apps, both free and paid, that allow you to lock individual app and prevent unauthorized access. In Make Tech Easier, I have even recommended a few app-locker, including ZDBox, Seal and Widget Locker. The question is, how reliable are these apps? Can you depend on them to protect your phone?

How the App Locker works?

After you have installed the app locker, you will be able to choose which apps you want to protect and the unlock mode (password, pin or pattern). What the app does is to continuously monitor the running apps and see which one is freshly opened. If it fits the apps in the protect list, the app locker will intercept and show a challenge screen for you to unlock the app.

The Exploit

Let’s see how we can bypass or disable the app locker.

Let’s say you are using the app locker to protect some of the apps with personal data, like the File Manager, expense manager etc, but you didn’t lock up the “Settings” app. All I need to do is to go to “Settings -> Apps”, find the app locker and press the “Clear Data” button. Boom! All your protection is reset immediately. This doesn’t apply only to app locker, it applies to all apps that come with a PIN protection, particularly the Play Store app.


And more…

So you have decided that you should protect the “Settings” app as well and you will be safe after that. Hold that thought! The next thing I will do is to go to the App Drawer, find the app locker and drag it to the Uninstall bin. Boom! All your app protection is gone, again.

And if that is not possible, then I can go to the File Manager, System tools, or even Titanium Backup (these apps are commonly found in most Android phone) and make use of the Uninstall function to uninstall the app locker.

The solution

The solution is very easy. The app locker is useful only if you are protecting the correct apps. While there are plenty of app locking apps in the Play Store, not all of them are made equal. Some of them are way too simple to be of any use (and still charge you for it).

1. First, install an app locker that can protect the “Settings” app as well as protect against installation / uninstallation of apps.

2. Run the app locker and start to add the essential apps to the protect list. Here is the list of apps that you should protect:

  1. The Settings app
  2. Package Installer – protect against installation and uninstallation of apps
  3. Play Store app and any other AppStore app (such as Amazon AppStore)
  4. Any app that have the ability to install/uninstall apps – such as File Manager, Titanium Backup, System Tools etc
  5. Online storage drive such as Dropbox, Box, Drive, Skydrive, Sugarsync etc

and of course, any other app that contain your confidential data.

As an additional security, you should also disable the ability to install app from unknown source. Enable it only when you need to, and disable it again once you are done.


The app locker is as secure as you allow it to be. If you don’t bother to lock up the necessary apps, it doesn’t matter how much you pay for the app locker, they are useless at the end of the day.

Image credit: Norebbo

Damien Damien

Damien Oh started writing tech articles since 2007 and has over 10 years of experience in the tech industry. He is proficient in Windows, Linux, Mac, Android and iOS, and worked as a part time WordPress Developer. He is currently the owner and Editor-in-Chief of Make Tech Easier.


  1. what if I put passwords for settings, file manager, install/uninstall then how can I bypass it???

    1. As I mentioned in the article, “The app locker is useful only if you are protecting the correct apps.”. In addition, to protecting Settings, File Manager, Install/Uninstall, you will also have to protect apps that can wipe your phone or uninstall app (like Titanium Backup). You also have to use a secure password that is not easily crackable.

      1. Question, how long does it take for Application Protect to start. On my Galaxy S4 it takes to long, so you can get into settings right before it starts and simply uninstall the app. Is there a way around this?

        1. @Paul, there are tons of app locker in the Play store. Have you try out other that have better performance? Application Protect works fine on my phone, but the performance may vary in different phones and settings.

  2. Hi, I can’t protect the “Settings” because my daughter needs to use her phone and change the rings, etc. I got her a touch screen phone Galaxy 4 but we don’t want her having access to internet, yet the wifi is active if I don’t block the settings.
    Is it still possible to lock virtually all of the other apps on the phone and not worry that she can get around this by not locking the “settings” app? I’d appreciate your reply.
    Thank you!

    1. chani, you can still use app locker to lock other apps, but you have to pray that your daughter didn’t read this article and find out the way to get around it.

      1. yes I locked practically all of the other apps. If that’s the case, how could she get around loading anything onto her phone since install/uninstall is locked? Please explain, thank you!

        1. The Play Store is not the only way to install apps. If she has access to the Settings, she could allow the “Install from unknown sources” and she just has to download the apk file from the web to install it in the phone. The same goes for uninstallation. She can do that in the Settings.

  3. thanks for the info. while i dont think she would know how to do that I’m sure she can ask someone who may. the question then would be, is there a way for her to access or control “sound” settings other than “settings”? that seems to be the main reason i think she needs access to “settings” at this point. if theres a work-around for the sound i can close off “settings” to make it more secure. unless you have a better suggestion?

    1. Personally, I am using a Sound Profile app ( to control all my sound and volume settings. You might want to try it out.

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