Develop Reference

Preventing an android app being cloned by an app cloner

Created an app that used the device's uniqueID which is fetched by the following code snippet
String deviceId = Settings.Secure.getString(getContentResolver(),
Settings.Secure.ANDROID_ID);
When the user tries to clone the app by app cloner, then it creates a different deviceID and the app is not allowed to work
Is there any way to make our app non clonable
or
Any possible way to have the same deviceId even if the app instance is cloned?
Is there any way to find out whether the app is running in a cloned instance?

Applications like Cloner usually change your application's package name so you can retrieve package name and check if it is changed or not.
if (!context.getPackageName().equals("your.package.name")){
// close the app or do whatever
}
Also they usually sign cloned apk so the signature might be different from yours, you can check if signature is changed or not. I usually use this function:
#SuppressLint("PackageManagerGetSignatures")
public static int getCertificateValue(Context ctx){
try {
Signature[] signatures = null;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
try {
signatures = ctx.getPackageManager().getPackageInfo(ctx.getPackageName(), PackageManager.GET_SIGNING_CERTIFICATES).signingInfo.getApkContentsSigners();
}catch (Throwable ignored){}
}
if (signatures == null){
signatures = ctx.getPackageManager().getPackageInfo(ctx.getPackageName(), PackageManager.GET_SIGNATURES).signatures;
}
int value = 1;
for (Signature signature : signatures) {
value *= signature.hashCode();
}
return value;
} catch (Exception e) {
e.printStackTrace();
}
return 0;
}
public static boolean checkCertificate(Context ctx, int trustedValue){
return getCertificateValue(ctx) == trustedValue;
}
Before releasing your app call getCertificateValue(context) and write down the value and alongside with package name, check if that value matches the value that you get in runtime.
PS: as #vladyslav-matviienko said hackers will always find a way so try to make cloning harder by running some obfuscations on hardcoded package name and that value. Also try to tangle and spread these kind of logics all around the source code.

I found a story in proandroiddev by Siddhant Panhalkar and with some minor changes it's work perfectly in Mi device I did checked in Mi phones default Dual apps and some third party apps from playstore and it prevents from cloning (means not working properly after clone).
private const val APP_PACKAGE_DOT_COUNT = 3 // number of dots present in package name
private const val DUAL_APP_ID_999 = "999"
private const val DOT = '.'
fun CheckAppCloning(activity: Activity) {
val path: String = activity.filesDir.getPath()
if (path.contains(DUAL_APP_ID_999)) {
killProcess(activity)
} else {
val count: Int = getDotCount(path)
if (count > APP_PACKAGE_DOT_COUNT) {
killProcess(activity)
}
}
}
private fun getDotCount(path: String): Int {
var count = 0
for (element in path) {
if (count > APP_PACKAGE_DOT_COUNT) {
break
}
if (element == DOT) {
count++
}
}
return count
}
private fun killProcess(context: Activity) {
context.finish()
android.os.Process.killProcess( android.os.Process.myPid())
}

Detect if new install or updated version (Android app)

I have an app on the Play Store. I want to put a requirement that if users want to use a certain part of the app, they have to invite a friend before being able to do so. But I only want to impose this restriction to new installs of the app (to be fair to users that have installed the app before the restriction).
Sorry for the long intro, my question is how can I find out if the current device has updated the app or is a new install?

public static boolean isFirstInstall(Context context) {
try {
long firstInstallTime = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).firstInstallTime;
long lastUpdateTime = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).lastUpdateTime;
return firstInstallTime == lastUpdateTime;
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
return true;
}
}
public static boolean isInstallFromUpdate(Context context) {
try {
long firstInstallTime = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).firstInstallTime;
long lastUpdateTime = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).lastUpdateTime;
return firstInstallTime != lastUpdateTime;
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
return false;
}
}

The only solution I can see that doesn't involve an entity outside of the device would be to get the PackageInfo for your app and check the values of
versionCode
firstInstallTime
lastUpdateTime
On first install, firstInstallTime and lastUpdateTime will have the same value (at least on my device they were the same); after an update, the values will be different because lastUpdateTime will change. Additionally, you know approximately what date and time you create the version that introduces this new behavior, and you also know which version code it will have.
I would extend Application and implement this checking in onCreate(), and store the result in SharedPreferences:
public class MyApplication extends Application {
// take the date and convert it to a timestamp. this is just an example.
private static final long MIN_FIRST_INSTALL_TIME = 1413267061000L;
// shared preferences key
private static final String PREF_SHARE_REQUIRED = "pref_share_required";
#Override
public void onCreate() {
super.onCreate();
checkAndSaveInstallInfo();
}
private void checkAndSaveInstallInfo() {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
if (prefs.contains(PREF_SHARE_REQUIRED)) {
// already have this info, so do nothing
return;
}
PackageInfo info = null;
try {
info = getPackageManager().getPackageInfo(getPackageName(), 0);
} catch (NameNotFoundException e) {
// bad times
Log.e("MyApplication", "couldn't get package info!");
}
if (packageInfo == null) {
// can't do anything
return;
}
boolean shareRequired = true;
if (MIN_FIRST_INSTALL_TIME > info.firstInstallTime
&& info.firstInstallTime != info.lastUpdateTime) {
/*
* install occurred before a version with this behavior was released
* and there was an update, so assume it's a legacy user
*/
shareRequired = false;
}
prefs.edit().putBoolean(PREF_SHARE_REQUIRED, shareRequired).apply();
}
}
This is not foolproof, there are ways to circumvent this if the user really wants to, but I think this is about as good as it gets. If you want to track these things better and avoid tampering by the user, you should start storing user information on a server (assuming you have any sort of backend).

Check if the old version of your app saves some data on disk or preferences. This data must be safe, i.e. it cannot be deleted by the user (I'm not sure it's possible).
When the new version is freshly installed, this data won't exist. If the new version is an upgrade from the old version, this data will exist.
Worst case scenario, an old user will be flagged as a new one and will have a restricted usage.

A concise Kotlin solution, based off the still excellent wudizhuo answer:
val isFreshInstall = with(packageManager.getPackageInfo(packageName, 0)) {
firstInstallTime == lastUpdateTime
}
This can be called directly from within an Activity as an Activity is a context (so can access packageManager etc.)
If you wanted to use this in multiple places/contexts, it could very easily be turned into an extension property:
val Context.isFreshInstall get() = with(packageManager.getPackageInfo(packageName, 0)) {
firstInstallTime == lastUpdateTime
}
This way, you can simply write if (isFreshInstall) in any Activity, or if (requireContext().isFreshInstall) inside any Fragment.

My solution is use SharedPreference
private int getFirstTimeRun() {
SharedPreferences sp = getSharedPreferences("MYAPP", 0);
int result, currentVersionCode = BuildConfig.VERSION_CODE;
int lastVersionCode = sp.getInt("FIRSTTIMERUN", -1);
if (lastVersionCode == -1) result = 0; else
result = (lastVersionCode == currentVersionCode) ? 1 : 2;
sp.edit().putInt("FIRSTTIMERUN", currentVersionCode).apply();
return result;
}
return 3 posibles values:
0: The APP is First Install
1: The APP run once time
2: The APP is Updated

Update
(thanks for the comments below my answer for prodding for a more specific/complete response).
Because you can't really retroactively change the code for previous versions of your app, I think the easiest is to allow for all current installs to be grandfathered in.
So to keep track of that, one way would be to find a piece of information that points to a specific version of your app. Be that a timestamped file, or a SharedPreferences, or even the versionCode (as suggested by #DaudArfin in his answer) from the last version of the app you want to allow users to not have this restriction. Then you need to change this. That change then becomes your reference point for all the previous installs. For those users mark their "has_shared" flag to true. They become grandfathered in. Then, going forward, you can set the "has_shared" default to true
(Original, partial answer below)
Use a SharedPrefence (or similar)
Use something like SharedPreferences.
This way you can put a simple value like has_shared = true and SharedPreferences will persist through app updates.
Something like this when they have signed someone up / shared your app
SharedPreferences prefs = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();
editor.putBoolean("has_shared", true)
editor.commit();
Then you can only bug people when the pref returns true
SharedPreferences prefs = getActivity().getPreferences(Context.MODE_PRIVATE);
boolean defaultValue = false;
boolean hasShared= prefs.gettBoolean("has_shared", defaultValue);
if (!hasShared) {
askUserToShare();
}
Docs for SharedPreference:
http://developer.android.com/training/basics/data-storage/shared-preferences.html

You can get the version code and version name using below code snippet
String versionName = getPackageManager().getPackageInfo(getPackageName(), 0).versionName;
int versionCode = getPackageManager().getPackageInfo(getPackageName(), 0).versionCode;
Now you can check for the latest version and restrict as per your requirement.

We can use broadcast receiver to listen app update.
Receiver
class AppUpgradeReceiver : BroadcastReceiver() {
#SuppressLint("UnsafeProtectedBroadcastReceiver")
override fun onReceive(context: Context?, intent: Intent?) {
if (context == null) {
return
}
Toast.makeText(context, "Updated to version #${BuildConfig.VERSION_CODE}!", Toast.LENGTH_LONG).show()
}
}
Manifest
<receiver android:name=".AppUpgradeReceiver">
<intent-filter>
<action android:name="android.intent.action.MY_PACKAGE_REPLACED" />
</intent-filter>
It doesn't work while debug. So you have to install to manually.
Increase the versionCode in your app-level build.gradle (so it counts as an update).
Click Build -> Build Bundle(s) / APK(s) -> Build APK(s), and select a debug APK.
Run following command in the terminal of Android Studio:
adb install -r C:\Repositories\updatelistener\app\build\outputs\apk\debug\app-debug.apk

If you want to perform any operation only once per update then follow below code snippet
private void performOperationIfInstallFromUpdate(){
try {
SharedPreferences prefs = getActivity().getPreferences(Context.MODE_PRIVATE);
String versionName = prefs.getString(versionName, "1.0");
String currVersionName = getApplicationContext().getPackageManager().getPackageInfo(getPackageName(), 0).versionName;
if(!versionName.equals(currVersionName)){
//Perform Operation which want execute only once per update
//Modify pref
SharedPreferences.Editor editor = prefs.edit();
editor.putString(versionName, currVersionName);
editor.commit();
}
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
return BASE_VERSION;
}
}

Integrating and working with .pkpass passes in Xamarin Android app

I'm developing a Xamarin Android app and I need the ability to be able to work with Passes (PassKit passes for example (JSON)). I need to be able to list all the passes in a ListVew and be able to open and display the pass. Also be able to save them to a wallet such as PassWallet or Pass2u. I don't need the ability to create them, just view them, and save them to a wallet or discard them.
There seems to be an example Xamarin iOS app which does exactly what i need here but of course I need to be able to do this in Xamarin Android.
I've been researching this for hours but don't know how to achieve what i need. JSON.net seems the way to go to read the passes, but that's as far as I've managed to get. Some examples would be great. Can anybody help?

To add the pass into PassWallet you can use the following:
private static boolean launchPassWallet(Context applicationContext, Uri uri, boolean launchGooglePlay) {
if (null != applicationContext) {
PackageManager packageManager = applicationContext.getPackageManager();
if (null != packageManager) {
final String strPackageName = "com.attidomobile.passwallet";
Intent startIntent = new Intent();
startIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startIntent.setAction(Intent.ACTION_VIEW);
Intent passWalletLaunchIntent = packageManager
.getLaunchIntentForPackage(strPackageName);
if (null == passWalletLaunchIntent) {
// PassWallet isn't installed, open Google Play:
if (launchGooglePlay) {
String strReferrer = "";
try {
strReferrer = "&referrer=" + URLEncoder.encode(uri.toString(), "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
strReferrer = "";
}
try {
startIntent.setData(Uri.parse("market://details?id=" + strPackageName + strReferrer));
applicationContext.startActivity(startIntent);
} catch (android.content.ActivityNotFoundException anfe) {
// Google Play not installed, open via website
startIntent.setData(Uri.parse("http://play.google.com/store/apps/details?id=" + strPackageName + strReferrer));
applicationContext.startActivity(startIntent);
}
}
} else {
final String strClassName = "com.attidomobile.passwallet.activity.TicketDetailActivity";
startIntent.setClassName(strPackageName, strClassName);
startIntent.addCategory(Intent.CATEGORY_BROWSABLE);
startIntent.setDataAndType(uri, "application/vnd.apple.pkpass");
applicationContext.startActivity(startIntent);
return true;
}
}
}
return false;
}
And an example call is:
launchPassWallet(getApplicationContext(),Uri.parse("http://test.attidomobile.com/PassWallet/Passes/AttidoMobile.pkpass"), true);
You can also use a file:// URL if you have the file locally.
To display them in the list, you'd need to unzip the .pkpass file and then parse the JSON for the relevant fields.

What is android:sharedUserLabel and what added value does it add on top of android:sharedUserID?

The documentation (http://developer.android.com/guide/topics/manifest/manifest-element.html#uid) only states I can't use raw strings and the API level it was added, but doesn't explain why I would want to use it.
If I already set android:sharedUserID to "com.foo.bar" what value should I put in the string referenced by android:sharedUserLabel, and most importantly why!?
Thank you

As far as I understand from the AOSP actually you can use this label just to display a pretty name to a user (if you have several processes in the same uid). For instance, here is a part of code in the RunningState.java file:
// If we couldn't get information about the overall
// process, try to find something about the uid.
String[] pkgs = pm.getPackagesForUid(mUid);
// If there is one package with this uid, that is what we want.
if (pkgs.length == 1) {
try {
ApplicationInfo ai = pm.getApplicationInfo(pkgs[0], 0);
mDisplayLabel = ai.loadLabel(pm);
mLabel = mDisplayLabel.toString();
mPackageInfo = ai;
return;
} catch (PackageManager.NameNotFoundException e) {
}
}
// If there are multiple, see if one gives us the official name
// for this uid.
for (String name : pkgs) {
try {
PackageInfo pi = pm.getPackageInfo(name, 0);
if (pi.sharedUserLabel != 0) {
CharSequence nm = pm.getText(name,
pi.sharedUserLabel, pi.applicationInfo);
if (nm != null) {
mDisplayLabel = nm;
mLabel = nm.toString();
mPackageInfo = pi.applicationInfo;
return;
}
}
} catch (PackageManager.NameNotFoundException e) {
}
}
Basically, it does the following things. At first, it tries to get information about the overall process. If it has not find, it tries to get information using UID of the application as a parameter (this is a part of code that I've given here). If there is only one package with this UID the information about the process is got from this package. But if there are several packages (using shareUserId) then it iterates and tries to find official (pretty) name.
As a confirmation to my words I found the following string in MediaProvider:
<!-- Label to show to user for all apps using this UID. -->
<string name="uid_label">Media</string>
Thus, all process that uses android:sharedUserId="android.media" will have name Media.
I do not think that this feature will be used a lot by ordinary developers and is useful for them.

install / uninstall APKs programmatically (PackageManager vs Intents)

My application installs other applications, and it needs to keep track of what applications it has installed. Of course, this could be achieved by simply keeping a list of installed applications. But this should not be necessary! It should be the responsibility of the PackageManager to maintain the installedBy(a, b) relationship. In fact, according to the API it is:
public abstract String getInstallerPackageName(String packageName) -
Retrieve the package name of the application that installed a package. This identifies which market the package came from.
The current approach
Install APK using Intent
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(apkUri, "application/vnd.android.package-archive");
startActivity(intent);
Uninstall APK using Intent:
Intent intent = new Intent(Intent.ACTION_DELETE, Uri.fromParts("package",
getPackageManager().getPackageArchiveInfo(apkUri.getPath(), 0).packageName,null));
startActivity(intent);
This is obviously not the way e.g. Android Market installs / uninstalls packages. They use a richer version of the PackageManager. This can bee seen by downloading the Android source code from the Android Git repository. Below are the two hidden methods that corresponds to the Intent approach. Unfortunately they are not available to external developers. But perhaps they will be in the future?
The better approach
Installing APK using the PackageManager
/**
* #hide
*
* Install a package. Since this may take a little while, the result will
* be posted back to the given observer. An installation will fail if the calling context
* lacks the {#link android.Manifest.permission#INSTALL_PACKAGES} permission, if the
* package named in the package file's manifest is already installed, or if there's no space
* available on the device.
*
* #param packageURI The location of the package file to install. This can be a 'file:' or a
* 'content:' URI.
* #param observer An observer callback to get notified when the package installation is
* complete. {#link IPackageInstallObserver#packageInstalled(String, int)} will be
* called when that happens. observer may be null to indicate that no callback is desired.
* #param flags - possible values: {#link #INSTALL_FORWARD_LOCK},
* {#link #INSTALL_REPLACE_EXISTING}, {#link #INSTALL_ALLOW_TEST}.
* #param installerPackageName Optional package name of the application that is performing the
* installation. This identifies which market the package came from.
*/
public abstract void installPackage(
Uri packageURI, IPackageInstallObserver observer, int flags,
String installerPackageName);
Uninstalling APK using the PackageManager
/**
* Attempts to delete a package. Since this may take a little while, the result will
* be posted back to the given observer. A deletion will fail if the calling context
* lacks the {#link android.Manifest.permission#DELETE_PACKAGES} permission, if the
* named package cannot be found, or if the named package is a "system package".
* (TODO: include pointer to documentation on "system packages")
*
* #param packageName The name of the package to delete
* #param observer An observer callback to get notified when the package deletion is
* complete. {#link android.content.pm.IPackageDeleteObserver#packageDeleted(boolean)} will be
* called when that happens. observer may be null to indicate that no callback is desired.
* #param flags - possible values: {#link #DONT_DELETE_DATA}
*
* #hide
*/
public abstract void deletePackage(
String packageName, IPackageDeleteObserver observer, int flags);
Differences
When using intents the local package manager is not made aware of which application the installation originated from. Specifically, getInstallerPackageName(...) returns null.
The hidden method installPackage(...) takes the installer package name as a parameter, and is most likely capable of setting this value.
Question
Is it possible to specify package installer name using intents?
(Maybe the name of the installer package can be added as an extra to the installation intent?)
Tip: If you want to download the Android source code you can follow the steps described here: Downloading the Source Tree. To extract the *.java files and put them in folders according to the package hierarchy you can check out this neat script: View Android Source Code in Eclipse.

Android P+ requires this permission in AndroidManifest.xml
<uses-permission android:name="android.permission.REQUEST_DELETE_PACKAGES" />
Then:
Intent intent = new Intent(Intent.ACTION_DELETE);
intent.setData(Uri.parse("package:com.example.mypackage"));
startActivity(intent);
to uninstall. Seems easier...

This is not currently available to third party applications. Note that even using reflection or other tricks to access installPackage() will not help, because only system applications can use it. (This is because it is the low-level install mechanism, after the permissions have been approved by the user, so it is not safe for regular applications to have access to.)
Also the installPackage() function arguments have often changed between platform releases, so anything you do trying access it will fail on various other versions of the platform.
EDIT:
Also it is worth pointing out that this installerPackage was only added fairly recently to the platform (2.2?) and was originally not actually used for tracking who installed the app -- it is used by the platform to determine who to launch when reporting bugs with the app, for implementing Android Feedback. (This was also one of the times the API method arguments changed.) For at least a long while after it was introduced, Market still didn't use it to track the apps it has installed (and it may very well still not use it), but instead just used this to set the Android Feedback app (which was separate from Market) as the "owner" to take care of feedback.

API level 14 introduced two new actions: ACTION_INSTALL_PACKAGE and ACTION_UNINSTALL_PACKAGE. Those actions allow you to pass EXTRA_RETURN_RESULT boolean extra to get an (un)installation result notification.
Example code for invoking the uninstall dialog:
String app_pkg_name = "com.example.app";
int UNINSTALL_REQUEST_CODE = 1;
Intent intent = new Intent(Intent.ACTION_UNINSTALL_PACKAGE);
intent.setData(Uri.parse("package:" + app_pkg_name));
intent.putExtra(Intent.EXTRA_RETURN_RESULT, true);
startActivityForResult(intent, UNINSTALL_REQUEST_CODE);
And receive the notification in your Activity#onActivityResult method:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == UNINSTALL_REQUEST_CODE) {
if (resultCode == RESULT_OK) {
Log.d("TAG", "onActivityResult: user accepted the (un)install");
} else if (resultCode == RESULT_CANCELED) {
Log.d("TAG", "onActivityResult: user canceled the (un)install");
} else if (resultCode == RESULT_FIRST_USER) {
Log.d("TAG", "onActivityResult: failed to (un)install");
}
}
}

If you have Device Owner (or profile owner, I haven't tried) permission you can silently install/uninstall packages using device owner API.
for uninstalling:
public boolean uninstallPackage(Context context, String packageName) {
ComponentName name = new ComponentName(MyAppName, MyDeviceAdminReceiver.class.getCanonicalName());
PackageManager packageManger = context.getPackageManager();
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
PackageInstaller packageInstaller = packageManger.getPackageInstaller();
PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
PackageInstaller.SessionParams.MODE_FULL_INSTALL);
params.setAppPackageName(packageName);
int sessionId = 0;
try {
sessionId = packageInstaller.createSession(params);
} catch (IOException e) {
e.printStackTrace();
return false;
}
packageInstaller.uninstall(packageName, PendingIntent.getBroadcast(context, sessionId,
new Intent("android.intent.action.MAIN"), 0).getIntentSender());
return true;
}
System.err.println("old sdk");
return false;
}
and to install package:
public boolean installPackage(Context context,
String packageName, String packagePath) {
ComponentName name = new ComponentName(MyAppName, MyDeviceAdminReceiver.class.getCanonicalName());
PackageManager packageManger = context.getPackageManager();
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP) {
PackageInstaller packageInstaller = packageManger.getPackageInstaller();
PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
PackageInstaller.SessionParams.MODE_FULL_INSTALL);
params.setAppPackageName(packageName);
try {
int sessionId = packageInstaller.createSession(params);
PackageInstaller.Session session = packageInstaller.openSession(sessionId);
OutputStream out = session.openWrite(packageName + ".apk", 0, -1);
readTo(packagePath, out); //read the apk content and write it to out
session.fsync(out);
out.close();
System.out.println("installing...");
session.commit(PendingIntent.getBroadcast(context, sessionId,
new Intent("android.intent.action.MAIN"), 0).getIntentSender());
System.out.println("install request sent");
return true;
} catch (IOException e) {
e.printStackTrace();
return false;
}
}
System.err.println("old sdk");
return false;
}

The only way to access those methods is through reflection. You can get a handle on a PackageManager object by calling getApplicationContext().getPackageManager() and using reflection access these methods. Checkout this tutorial.

According to Froyo source code, the Intent.EXTRA_INSTALLER_PACKAGE_NAME extra key is queried for the installer package name in the PackageInstallerActivity.

On a rooted device, you might use:
String pkg = context.getPackageName();
String shellCmd = "rm -r /data/app/" + pkg + "*.apk\n"
+ "rm -r /data/data/" + pkg + "\n"
// TODO remove data on the sd card
+ "sync\n"
+ "reboot\n";
Util.sudo(shellCmd);
Util.sudo() is defined here.

If you are passing package name as parameter to any of your user defined function then use the below code :
Intent intent=new Intent(Intent.ACTION_DELETE);
intent.setData(Uri.parse("package:"+packageName));
startActivity(intent);

If you're using Kotlin, API 14+, and just wish to show uninstall dialog for your app:
startActivity(Intent(Intent.ACTION_UNINSTALL_PACKAGE).apply {
data = Uri.parse("package:$packageName")
})
You can change packageName to any other package name if you want to prompt the user to uninstall another app on the device

Prerequisite:
Your APK needs to be signed by system as correctly pointed out earlier. One way to achieve that is building the AOSP image yourself and adding the source code into the build.
Code:
Once installed as a system app, you can use the package manager methods to install and uninstall an APK as following:
Install:
public boolean install(final String apkPath, final Context context) {
Log.d(TAG, "Installing apk at " + apkPath);
try {
final Uri apkUri = Uri.fromFile(new File(apkPath));
final String installerPackageName = "MyInstaller";
context.getPackageManager().installPackage(apkUri, installObserver, PackageManager.INSTALL_REPLACE_EXISTING, installerPackageName);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
Uninstall:
public boolean uninstall(final String packageName, final Context context) {
Log.d(TAG, "Uninstalling package " + packageName);
try {
context.getPackageManager().deletePackage(packageName, deleteObserver, PackageManager.DELETE_ALL_USERS);
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
To have a callback once your APK is installed/uninstalled you can use this:
/**
* Callback after a package was installed be it success or failure.
*/
private class InstallObserver implements IPackageInstallObserver {
#Override
public void packageInstalled(String packageName, int returnCode) throws RemoteException {
if (packageName != null) {
Log.d(TAG, "Successfully installed package " + packageName);
callback.onAppInstalled(true, packageName);
} else {
Log.e(TAG, "Failed to install package.");
callback.onAppInstalled(false, null);
}
}
#Override
public IBinder asBinder() {
return null;
}
}
/**
* Callback after a package was deleted be it success or failure.
*/
private class DeleteObserver implements IPackageDeleteObserver {
#Override
public void packageDeleted(String packageName, int returnCode) throws RemoteException {
if (packageName != null) {
Log.d(TAG, "Successfully uninstalled package " + packageName);
callback.onAppUninstalled(true, packageName);
} else {
Log.e(TAG, "Failed to uninstall package.");
callback.onAppUninstalled(false, null);
}
}
#Override
public IBinder asBinder() {
return null;
}
}
/**
* Callback to give the flow back to the calling class.
*/
public interface InstallerCallback {
void onAppInstalled(final boolean success, final String packageName);
void onAppUninstalled(final boolean success, final String packageName);
}