Develop Reference

App not receiving boot completed intent in some devices

i created an app that always start a service once the device has completed booting.
This is the Manifest code..
<receiver>
android:name="StartMyServiceAtBootReceiver"
android:directBootAware ="true"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
<action android:name="android.intent.action.LOCKED_BOOT_COMPLETED" />
<action android:name="android.intent.action.REBOOT"/>
<action android:name="android.intent.action.QUICKBOOT_POWERON" />
</intent-filter>
</receiver>
The service always start in some devices once boot is completed but in my own device which is running android 7.0, the boot completed service doesn't start unless i convert the app to system app using root access. Can someone tell me how to make the app to start the service on boot completed without converting it to a system app?

First of All
receiver android:name="StartMyServiceAtBootReceiver"
Your path to Receiver should written over here for example:
<receiver android:name=".receiver.BootReceiver">
first dot suggest your path till root of the package.
Create a BroadcastReceiver and register it to receive ACTION_BOOT_COMPLETED. You also need RECEIVE_BOOT_COMPLETED permission.
Read: Listening For and Broadcasting Global Messages , and Setting Alarms

Try into manifest
<receiver
android:name=".AutoStart"
android:enabled="true"
android:exported="true" >
<intent-filter android:priority="500" >
<action android:name="android.intent.action.BOOT_COMPLETED" />
<action android:name="android.intent.action.QUICKBOOT_POWERON" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</receiver>
Make sure also to include the completed boot permission.
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
Also read this answer carefully

Manifest-declared broadcast receiver does not receive custom broadcast on Android 8

First, I created a BroadcastReceiver with empty body. Then, I added it to the AndroidManifest.xml. But I found out that BroadcastReceiver declared in manifest does not receive any broadcast. I sent broadcast by
sendOrderedBroadcast(new Intent("com.example.action"), null)
or
adb shell am broadcast -a com.example.action
Both methods works on Android 7 but it does not work on Android 8. However, if the BroadcastReceiver is declared through registerReceiver, then it can still receive the broadcast.
On the other hand, android.hardware.usb.action.USB_DEVICE_ATTACHED works fine on both Android 7 and 8.
I want to ask why does it happen? I have tested it in both emulator and a physical device. They have the same behavior.
AndroidManifest.xml
...
<receiver
android:name=".device.UsbBroadcastReceiver"
android:exported="true">
<intent-filter>
<action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
<action android:name="com.example.action" />
</intent-filter>
<meta-data
android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
android:resource="#xml/device_filter" />
</receiver>
...

As part of the Android 8.0 (API level 26) Background Execution Limits, apps that target the API level 26 or higher can no longer register broadcast receivers for implicit broadcasts in their manifest.
Read this

Manifest Based broadcast working for me in android 8
Broadcast restriction by android is not applicable for all the broadcasts some can still be registered inside manifest . But do check latest documentation since these may way depending on android version .
<receiver
android:name=".UsbReceiver"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
</intent-filter>
<intent-filter>
<action android:name="android.hardware.usb.action.USB_DEVICE_DETACHED" />
</intent-filter>
<meta-data
android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
android:resource="#xml/device_filter" />

Handle network configuration sms

I want to handle received sms that contains network configurations(OMA OTA). I have already developed android application that catches typical sms from inbox. Network configuration is not a typical sms. How can I get it? What is a Broadcast Action for that?
I was trying this:
<receiver android:name="ru.tenet.pdureceiver.SMSReceiver" >
<intent-filter android:priority="1" >
<action android:name="android.provider.Telephony.SMS_RECEIVED" />
</intent-filter>
</receiver>
As I understood, android.provider.Telephony.SMS_RECEIVED is not enough.

Well, I've found a solution. The action is:
android.provider.Telephony.WAP_PUSH_RECEIVED
And also there must be a mimeType defined for wap message.
For example:
<intent-filter android:priority="1" >
<action android:name="android.provider.Telephony.WAP_PUSH_RECEIVED" />
<data android:mimeType="application/vnd.wap.connectivity-wbxml" />
</intent-filter>

Track Applications on Android

is it possible to keep track of install/uninstall actions of Applications on the Android system? I was not able to find a proper Intent Action or Broadcast event so far.
What I'm searching for an observer for applications like there are observers for Calendar or CallLog changes. Does there exists an CONTENT_URI or Broadcast event?
Regards

You can create a broadcast receiver for package install and unistall.
<receiver android:name=".YourReceiver">
<intent-filter>
<action android:name="android.intent.action.PACKAGE_INSTALL" />
<action android:name="android.intent.action.PACKAGE_ADDED" />
<action android:name="android.intent.action.PACKAGE_REMOVED" />
<data android:scheme="package"/>
</intent-filter>
</receiver>
For More info go to link

Android unregisterReceiver with onPause

I have something like this in my manifest file - I need one receiver for the situation that a power source was connected and the other receiver for unplugged source.
<receiver android:name=".PowerConnectionOnReceiver" >
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_CONNECTED" />
</intent-filter>
</receiver>
<receiver android:name=".PowerConnectionOffReceiver" >
<intent-filter>
<action android:name="android.intent.action.ACTION_POWER_DISCONNECTED" />
</intent-filter>
</receiver>
But I want to unregisterReceiver, when onPause is called in my MainActivity. How to do it?

If your broadcast receiver is specified in the manifest, it cannot be unregistered programmatically. You will need to take it out of the manifest and register it from within your code.

You cannot unregister these receivers because they are defined in manifest, not in code. Receivers which are defined programmatically are the one which may get unregistered.