Mikhail Varakin
teacher of the Center computer training"Specialist"
at MSTU named after. N.E. Bauman

As its market share in mobile devices increases, the Android platform is becoming increasingly attractive to enterprise application developers. At the same time, the corporate environment is characterized by the need to comply with policies that ensure the required level of security information systems. IN Android API 8 (Android 2.2) for the first time, support for corporate applications appeared using the Device Administration API, which provides the ability to administer devices on Android platform on system level. This API allows developers to create applications needed in a corporate environment where enterprise IS administrators need control over staff mobile devices. One of these applications is already available on everyone modern devices: built-in mail client uses Device Administration API when synchronizing with Microsoft Exchange and through this application, Exchange administrators can enforce password policies and remotely wipe data (factory reset) if a device is lost or stolen.

Organizational aspects of use

An application that uses the Device Administration API can be installed on a device in any way, such as through Google Play, and from other sources. Fact of availability installed application does not yet enforce the policies for which it was created - the user is required to agree to the application of administrative policies. In case of failure, the application will remain on the system and will be in an inactive state. As a rule, the user's consent to the use of policies provides him with useful features, for example, access to confidential information that would not be available in the event of a refusal. If the user does not comply with the current policies (for example, when using an insufficiently strong password), the application’s reaction is determined by what the developer considered necessary to implement; usually the user loses the ability to use corporate services. When using the administration mechanism in corporate environments, keep the following points in mind:

• when trying to connect to a service that requires compliance with a specific set of policies, not all of which are supported mobile device(for example, due to outdated Android versions), the connection will not be established;
• if several applications that use the Device Administration API are activated on the device, the most strict restrictions, imposed by administration policies used in these applications;
• in addition to various restrictions regarding passwords (complexity, expiration period, number of entry attempts), maximum inactivity time before locking the screen, requirements for media encryption and prohibition of using the camera, in currently Device Administration API provides additional features: Password change requirement, immediate screen lock and factory reset (with option to clear) external storage– SD cards);
• user concerns regarding the ability of company administrators to access personal data and correspondence, passwords of device owners in in social networks etc. are completely groundless: the Device Administration API does not provide such capabilities.

How it works

Currently, the Device Administration API contains three classes that are the basis for full-featured device administration applications:

• DeviceAdminReceiver: base class for classes that implement administration policies; The callback methods of this class provide convenient means to describe reactions to certain events related to politicians - individual “message receivers” for different events;
• DevicePolicyManager: class for managing policies applied on the device;
• DeviceAdminInfo: class used to describe metadata.

The main application logic is implemented in a class that extends the DeviceAdminReceiver class, which is a descendant of the BroadcastReceiver class. It is important to remember here that the callback methods of our class are executed in the main application thread (UI thread), so performing lengthy operations in them is unacceptable due to the risk of blocking the user interface. All necessary “long-running” actions must be performed in another thread (or even in a separate service). Like a regular BroadcastReceiver, our class must be described in the application manifest:

. . .
android:name=".MyDeviceAdminReceiver"
android:permission="android.permission.BIND_DEVICE_ADMIN"
android:name="android.app.device_admin"
android:resource="@xml/device_admin_data" />

android:name="android.app.action.DEVICE_ADMIN_ENABLED"/>


. . .

As you can see in the example, our receiver will receive messages with action equal to ACTION_DEVICE_ADMIN_ENABLED. In order for only the system to send us such messages, we require BIND_DEVICE_ADMIN permissions (these permissions are not granted to applications). The meta-data element contains a reference to a resource containing the policies supported by the application. In our case, the path to the XML file is: res/xml/device_admin_data. Sample contents of the file are shown below:

The child elements in uses-policies describe the types of policies used in the application. A complete list of possible policies can be found in the constants of the DeviceAdminInfo class, including on developer.android.com: http://developer.android.com/reference/android/app/admin/DeviceAdminInfo.html.

Let's look at an example implementation of the administration component:

public class MyDeviceAdminReceiver extends DeviceAdminReceiver (

@Override
public void onDisabled(Context context, Intent intent) (
super.onDisabled(context, intent);
// Called before this application stops
// be a device administrator (will be disabled
// by user).
}

@Override
public void onEnabled(Context context, Intent intent) (

// Called when the user has allowed to use
// this application is the device administrator.
// DevicePolicyManager can be used here
// to set administration policies.
}

@Override
public void onPasswordChanged(Context context, Intent intent) (
super.onPasswordChanged(context, intent);
// Called after the user changes the password.
// Does the new password comply with the policies,
// can be found using the method
// DevicePolicyManager.isActivePasswordSufficient()
}

@Override
public void onPasswordExpiring(Context context, Intent intent) (
super.onPasswordExpiring(context, intent);
// Called several times as time approaches
// password aging: when you turn on the device, once a day
// before the password expires and at the moment the password expires.
// If the password has not been changed since expiration, the method
// called once a day
}

@Override
public void onPasswordFailed(Context context, Intent intent) (
super.onPasswordFailed(context, intent);
// Called when an incorrect password is entered.
// The number of failed password attempts can be found
// using the getCurrentFailedPasswordAttempts() method
// class DevicePolicyManager.
}
. . .
}

To manage policies in an application, you need to get a reference to the policy manager (note that context is passed to the methods shown above as a parameter):

DevicePolicyManager dpm = (DevicePolicyManager) context

In the future, this manager will be used to set policies. The onEnabled() method, which sets the required password quality, could look something like this:

@Override
public void onEnabled(Context context, Intent intent) (
super.onEnabled(context, intent);
DevicePolicyManager dpm = (DevicePolicyManager) context
.getSystemService(Context.DEVICE_POLICY_SERVICE);
ComponentName cn = new ComponentName(context, getClass())

dpm.setPasswordQuality(cn, DevicePolicyManager.
PASSWORD_QUALITY_NUMERIC);

Settings for other password parameters are made using the corresponding DevicePolicyManager methods:

dpm.setPasswordMinimumLength(cn, 32);
dpm.setPasswordHistoryLength(cn, 10);
dpm.setPasswordExpirationTimeout(cn, 864000000L);

In addition to setting policies, DevicePolicyManager allows you to perform other operations (of course, not in the onEnabled() method):

• instant screen lock:
  dpm.lockNow();
• Factory reset with SD card clear:
  dpm.wipeData(DevicePolicyManager.WIPE_EXTERNAL_STORAGE);
• camera lock:
  dpm.setCameraDisabled(cn, true);

Additional Information

A deployed working sample application can be found in the Android SDK package (<путь-к-SDK>/samples/android-<версия-API/ApiDemos/).

The website developer.android.com has articles on this topic in the Training sections: http://developer.android.com/training/enterprise/device-management-policy.html and API Guides: http://developer.android.com /guide/topics/admin/device-admin.html.

Descriptions of the classes of the android.app.admin package on the same site: http://developer.android.com/guide/topics/admin/device-admin.html.

You can learn how to develop mobile applications for Android at.

The firmware of many smartphones and tablets running Android contains so-called bloatware: applications pre-installed by the manufacturer of dubious usefulness. As a rule, it is not possible to remove them in the usual way. Therefore, today we want to tell you how to uninstall such programs.

In addition to bloatware, virus software cannot be removed in the usual way: malicious applications use loopholes in the system to pretend to be the administrator of a device for which the uninstallation option is blocked. In some cases, for the same reason, it will not be possible to remove a completely harmless and useful program like: it needs administrator rights for some options. System applications like the Google search widget, the standard dialer, or the default one are also protected from uninstallation.

The actual methods for removing uninstallable applications depend on whether your device has root access. It is not required, but with such rights you will be able to get rid of unnecessary system software. Options for devices without root access are somewhat limited, but in this case there is a way out. Let's look at all the methods in more detail.

Method 1: Disable Administrator Rights

Many applications use elevated privileges to control your device, including screen lockers, alarm clocks, some launchers, and often viruses that masquerade as useful software. A program that has been granted access to Android administration cannot be uninstalled in the usual way - if you try to do this, you will see a message stating that uninstallation is impossible due to active device administrator options. What to do in this case? Here's what you need to do.

1. Make sure that developer options are enabled on your device. Go to "Settings".

   

   Pay attention to the very bottom of the list - such an option should be there. If it is not there, then do the following. At the very bottom of the list there is an item "About the phone". Enter it.

   

   Scroll to "Build number". Tap on it 5-7 times until you see a message about unlocking developer options.



2. Enable USB debugging mode in the developer settings. To do this, go to "Developer Options".

   

   Activate the options using the switch at the top, then scroll through the list and check the box next to "USB Debugging".



3. Return to the main settings window and scroll down the list of options to the general block. Tap on an item "Safety".

   

   On Android 8.0 and 8.1 this option is called "Location and Protection".



4. Next, you should find the device administrators option. On devices with Android version 7.0 and lower, it is called this "Device Administrators".

   

   In Android Oreo this feature is called "Device Administrator Applications" and is located almost at the very bottom of the window. Enter this settings item.



5. A list of applications that are allowed additional functions will appear. As a rule, there is remote device control, payment systems (S Pay, ), customization utilities, advanced alarm clocks and other similar software inside. There will probably be an application on this list that you can’t remove. To disable administrator privileges for him, tap on his name.

   

   On the latest versions of Google's OS, this window looks like this:



6. In Android 7.0 and below - there is a button in the lower right corner "Switch off", which you need to press.



In Android 8.0 and 8.1 - click on "Disable device admin app".



7. You will automatically return to the previous window. Please note that the check mark next to the program for which you have disabled administrator rights has disappeared.


This means that such a program can be removed in any available way.

This method allows you to get rid of most uninstallable applications, but may not be effective in the case of powerful viruses or bloatware embedded in the firmware.

Method 2: ADB + App Inspector

Complex, but the most effective method of getting rid of uninstallable software without root access. To use it, you will need to download and install Android Debug Bridge on your computer, and the App Inspector application on your phone.

Having done this, you can proceed to the procedure described below.

1. Connect your phone to your computer and install drivers for it, if necessary.
2. Make sure that the archive with ADB is unpacked to the root of the system disk. Then open "Command line": call "Start" and type the letters in the search field cmd. Right-click on the shortcut and select "Run as administrator".



3. In the window "Command line" write the commands sequentially:

   cd c:/adb
   adb devices
   adb shell



4. Go to the phone. Open App Inspector. A list of all applications available on your phone or tablet will be presented in alphabetical order. Find the one you want to delete among them and tap on its name.



5. Take a close look at the line "Package Name"— we will need the information recorded in it later.



6. Go back to your computer and "Command line". Type the following command in it:

   pm uninstall -k --user 0 *Package Name*

   

   Instead of *Package Name*, enter the information from the corresponding line from the page of the application to be removed in the App Inspector. Make sure the command is entered correctly and press Enter.

7. After the procedure, disconnect the device from the computer. The application will be deleted.

The only drawback of this method is that it removes the application only for the default user (the “user 0” operator in the command given in the instructions). On the other hand, this is a plus: if you deleted a system application and encountered problems with the device, it’s enough to simply do this to return the deleted one to its place.

Method 3: Titanium Backup (Root only)

If your device is rooted, the procedure for uninstalling uninstallable programs is greatly simplified: just install Titanium Backup, an advanced application manager that can remove almost any software, on your phone.

This method is the simplest and most convenient solution to the problem of uninstalling programs on Android. The only negative is that the free version of Titanium Backup is somewhat limited in its capabilities, which, however, are sufficient for the procedure described above.

Conclusion

As you can see, uninstallable applications are quite easy to deal with. Finally, let us remind you - do not install dubious software from unknown sources on your phone, as you risk running into a virus.

This can happen to anyone - when you try to delete an application, it turns out that it cannot be deleted. Moreover, in this case we are not talking about a built-in application in the firmware, which cannot be removed without root rights, but about the most common one, which you installed on your device.

For example, some time ago we talked about this and also showed an application called Volume Unlock, thanks to which you can turn on the device by pressing the volume up button. When running, the application receives administrator rights, so there is no easy way to remove it. But let’s show you clearly what it looks like.

Go to settings and find the “Applications” section.

Here we see a list of applications. Select the one you need (in our case, Volume Unlock).

And what do we see? That's right, the "Delete" button is inactive.

If you encounter a similar problem, no problem, it can be solved. To do this, go to Google Play and type in the search the word “uninstall” (without quotes) or uninstaller. Select an application from Rhythm Software and install it. This is an extremely small free application that does not even require additional rights.

After installing the application, open it and see a list of all installed applications. Select the one you need by tapping on it once, and then click on the “Delete selected applications” button, which is located at the top of the screen.

We agree with the deletion and see a window in front of us in which it is written: “It is impossible to delete the package because it is selected for device administration." Click “Administration Settings”.

A window opens and uncheck the application.

In a new window, disable the application’s administrative rights by clicking on the “Disable” button.

After this, we get to the application page and see that the “Delete” button is activated.

Click on it and the application is deleted.

Of course, this way you can remove virus applications that cannot be removed in the usual way. To remove system applications, you must have root rights.

Second way

For this method, we thank the user with the nickname Android, who in the comments suggested a less complicated method for removing such applications. He talked about another method that requires enabling USB debugging. A user with the nickname Valery reported that you can use this method without USB debugging, for which we thank him. And yet, we show an example with USB debugging - just in case. We advise you to immediately open the “Security” section (see the last three screenshots) and if this does not help, try enabling USB debugging.

Go to settings. Here, find the “About phone” (or “About tablet”) section.

After opening this section, it will appear in the settings:

Go into it and check the box next to “USB Debugging”.

Here you will see a check mark for an application that cannot be removed in the usual way.

Simply uncheck the box, then click Disable.

The application can now be uninstalled as usual.

I'm trying to remove the program from device administrators and it doesn't work. That is, I click on the name of the program, select Disable and the phone immediately turns off. After a minute or two it turns on, but the program remains the same as the administrator. This harmful program is a virus, that's why I want to disable it. Because otherwise it will not be deleted.

1. Install the KIS program from the Google Playmarket https://play.google.com/store/apps/details?id=com.kms.free or Malwarebytes Anti-malware https://play.google.com/store/apps/details? id=org.malwarebytes.antimalware
2. Launch and perform a full scan of your phone. This will take a long time, but be sure to wait for it to finish! When the scan is complete, remove the malware found.
3. Now try again to remove the malware from the device administrators. Open Phone Settings, then Security, then Device Administrators. Uncheck the box next to the malware. Confirm your actions. If a window appears with the message “To roll back updates, a full factory reset is required. All information on your device will be deleted..”, then feel free to click on OK. This message is only meant to scare you.
4. If step 3 was successful, then open the Applications section in your phone Settings and remove the malicious program.

Hello! I have a similar problem, only after I unchecked the checkbox, the phone began to ask for a PIN code on the main window. Doctor Web remained in the administrators and it looks like that application (called “Installation”, with the Avito icon). The phone works itself, calls, messages come, but I can’t go anywhere. When I restart the phone, sometimes a notification appears that an error has occurred in the Installation application. With or without the SIM, the phone still asks for a PIN code. I put the Android in safe mode, still the same...

Tell me what to do? (Android explay ALTO, firmware v1.00)

www.spyware-ru.com

How to delete an application on Android

Working with modern smartphones is usually quite simple. This is especially true for applications, namely installation using Google Play and removal through program settings. The situation is different when it comes to preinstalled ones that the smartphone or tablet manufacturer has safely installed. Most often, such software cannot be removed. What to do then?

There can be two reasons for this problem:

How to remove the device administrator program on Android

A device administrator is a software that has an extended list of powers and rights, unlike other ordinary applications. To the point that such a program can, if necessary, lock the phone and set passwords. But there is nothing to be afraid of, and you can deactivate it in the special menu “settings - security - device administrators”.

How to remove built-in system applications

Very often you can see how a smartphone manufacturer tries to “take care” of its users and install as many unnecessary and useless programs as possible. And besides, they tend to run in the background and drain the battery faster.

To solve the problem, you need to find the hated program in the settings, press the “Disable” button, clear the data and cache. After this, it will no longer appear in the menu, will not consume RAM and affect the operating time of the smartphone. It will not be possible to completely remove it using standard means - you need root rights. However, be careful when manipulating any system applications, this may affect the entire operation of the smartphone.

geekk.ru

How to get rid of uninstallable applications

Installing and uninstalling applications in the Android operating system is a very simple process, a few taps on the screen and you're done. However, there are applications that refuse to be removed. This situation occurs because some applications are installed as a device administrator, while others are already installed (pre-installed) by the device manufacturer and the user does not have rights to remove them.

To completely remove pre-installed applications, you will need root rights. If you don't want to root your device, you can try disabling pre-installed programs so that they don't start with Android and take up space in RAM. So, how to remove uninstallable applications.

Uninstalling admin apps on Android

Device administrator applications require more rights for their full functionality. This should not be confused with applications that require root rights, it’s just that administrator programs need more rights within the existing user rights. For example, to install protection or remotely block a smartphone, track it via GPS, etc.

If the application you installed is not uninstalled, then go to the settings of your Android device, go to the “Security” section and then to “Device Administrators”, in which uncheck the program being deleted that it is an administrator.

After this, the application will be uninstalled without any problems.

Removing or disabling pre-installed applications

There are manufacturers who abuse the installation of their programs that cannot be removed. You can delete them, as mentioned above, only by obtaining root rights on the device. But what to do if there is no desire to do this or the smartphone/tablet is under warranty and its root serves as the basis for removing the warranty? In this case, you can try stopping pre-installed applications. To do this, do the following:

Disabled pre-installed applications should disappear from the menu and will no longer run along with Android, and also take up RAM, which will be a big plus in budget smartphones, where it is always in short supply.

However, with system applications this procedure must be performed carefully, because You may encounter unstable operation of your device.

infodroid.ru

How to get rid of uninstallable applications?

The process of purchasing various apps from the Google Play Store is incredibly simple. To do this, you need to find the desired program or game, read the description and reviews of other users, after which you can safely click on the “Install” button. Uninstalling apps is no more difficult: it only takes a few clicks. However, from time to time the system refuses to remove certain programs, not to mention applications pre-installed by the manufacturer. How to get rid of this problem? Let's find out.

In general, there are two reasons for not deleting an application. In the case of the first, the annoying program can act as a device administrator. The second option is much more common, and each of us has probably encountered it. We are talking about applications that are part of the smartphone system. In other words, programs preinstalled by the company’s engineers, for which there is simply no delete key.

Our foreign colleagues from phonearena shared possible solutions to both of the problems described above. Let's look at each of them separately.

Administrator application

Don’t rush to close this article: there is nothing scary in this phrase. The fact is that some applications require more extensive permissions. For example, setting a password on a smartphone, blocking it, tracking geolocation and much, much more.

In this case, to remove them, just uncheck the special section of the menu. In my good old HTC One S, which I returned to use after the experience with the iPhone, to do this, go to settings - security - device administrators. One problem is solved, but what about the other?

System Application

Not all smartphone manufacturers love their users. The proof of this statement is the huge number of absolutely useless pre-installed applications that you have no desire to use. In a Taiwanese smartphone, again, similar ones include the EA Games icon, Friend Stream, Rescue, Teeter and other dubious programs.

Agree, it’s not so much their presence that’s annoying as the inability to get rid of them, right? However, it turns out that there was a way out of this situation.

To do this, you need to go to the application manager, select the hated program and find the “Disable” button. Following this, you can also clear the application cache.

The result will not be long in coming: the marked applications will disappear from the menu and will no longer remind you of themselves. However, it is not always possible to get rid of them completely: most likely, some programs will take up several megabytes in the memory card bins, but do not forget about the main advantage. A disabled application will not launch when the device is turned on, thereby saving RAM and, accordingly, device charge. Not bad, right?

Be that as it may, we should not forget that many system applications affect the operation of the smartphone as a whole, and therefore you should experiment with disabling them with extreme caution.

Apps in the Android operating system are a very simple process, a few taps on the screen and you're done. However, there are applications that refuse to be removed. This situation occurs because some applications are installed as a device administrator, while others are already installed (pre-installed) by the device manufacturer and the user does not have rights to remove them.

To completely remove pre-installed applications, you will need root rights. If you don't want to root your device, you can try disabling pre-installed programs so that they don't start with Android and take up space in RAM. So, how to remove uninstallable applications.

Device administrator applications require more rights for their full functionality. This should not be confused with applications that require , it’s just that administrator programs need more permissions within the framework of existing user rights. For example, to install protection or remotely block a smartphone, track it via GPS, etc.

If the application you installed is not uninstalled, then go to the settings of your Android device, go to the “ Safety" and further in " Device Administrators", in which uncheck the program being deleted that it is an administrator.

After this, the application will be uninstalled without any problems.

Removing or disabling pre-installed applications

There are manufacturers who abuse the installation of their programs that cannot be removed. You can delete them, as mentioned above, only by obtaining root rights on the device. But what to do if there is no desire to do this or the smartphone/tablet is under warranty and its root serves as the basis for removing the warranty? In this case, you can try stopping pre-installed applications. To do this, do the following:

Disabled pre-installed applications should disappear from the menu and will no longer run along with Android, and also take up RAM, which will be a big plus in budget smartphones, where it is always in short supply.