Install and Uninstall PackageInstaller

Intent filters for such actions are:

android:name=".PackageInstallerActivity">
>
android:name="android.intent.action.VIEW" />
android:name="android.intent.category.DEFAULT" />
android:scheme="content" />
android:scheme="file" />
android:mimeType="application/vnd.android.package-archive" />
>
>
 
android:name=".UninstallerActivity">
>
android:name="android.intent.action.VIEW" />
android:name="android.intent.action.DELETE" />
android:name="android.intent.category.DEFAULT" />
android:scheme="package" />
>
>

so if you want to install your .apk file from SD card – just write something like that:

String fileName = Environment.getExternalStorageDirectory() + "/myApp.apk";
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(fileName)), "application/vnd.android.package-archive");
startActivity(intent);

for uninstallation:

Uri packageURI = Uri.parse("package:com.android.myapp");
Intent uninstallIntent = new Intent(Intent.ACTION_DELETE, packageURI);
startActivity(uninstallIntent);

be aware that by default INSTALL_NON_MARKET_APPS option is disabled. You may want to check this option and show user friendly dialog before trying to install the app:

int result = Settings.Secure.getInt(getContentResolver(), Settings.Secure.INSTALL_NON_MARKET_APPS, 0);
if (result == 0) {
// show some dialog here
// ...
// and may be show application settings dialog manually
Intent intent = new Intent();
intent.setAction(Settings.ACTION_APPLICATION_SETTINGS);
startActivity(intent);
}