BOOT_COMPLETED

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.myapphere">

    <uses-sdk android:minSdkVersion="9" android:targetSdkVersion="9" />

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_PHONE_STATE" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    
    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" 
        android:theme="@android:style/Theme.NoTitleBar"
        android:name=".MyApp"
         >
        <activity
            android:name=".activity.LoginActivity" 
            android:label="@string/app_name" 
            android:screenOrientation="sensorPortait"
            android:windowSoftInputMode="stateAlwaysVisible|adjustResize">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        
        <activity
            android:name=".activity.MainActivity"
            android:label="@string/app_name"
            android:screenOrientation="sensorPortait" 
            android:windowSoftInputMode="adjustResize">
        </activity>
        
		<receiver
		    android:name=".receiver.BootCompletedReceiver"
		    android:enabled="true"
		    android:exported="true">
		    <intent-filter>
		        <action android:name="android.intent.action.BOOT_COMPLETED" />
		    </intent-filter>
		</receiver>
    </application>

</manifest>

BootCompletedReceiver.java

package com.myapphere;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;

public class BootCompletedReceiver extends BroadcastReceiver {
    private static final String TAG = BootCompletedReceiver.class.getSimpleName();
    
    @Override
    public void onReceive(Context context, Intent intent) {
        Log.i(TAG, "onReceive()");
        
        Intent intent = new Intent(context, LoginActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(intent);
    }
}

notes.txt

To launch an activity from a BroadcastReceiver you have to launch with NEW_TASK (exceptions apply). With that in mind you may want to look at the various launch mode options for the Activity in the AndroidManifest.