example of android manifest for main activity From http://developer.android.com/guide/components/intents-filters.html

androidmanifest_main_activity.xml

<activity android:name="MainActivity"> 
<!-- This activity is the main entry, should appear in app launcher -->
  <intent-filter> 
    <action android:name="android.intent.action.MAIN" />
    <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
    
</activity>
<activity android:name="ShareActivity">
  <!-- This activity handles "SEND" actions with text data -->
  <intent-filter>
    <action android:name="android.intent.action.SEND"/>
    <category android:name="android.intent.category.DEFAULT"/>
    <data android:mimeType="text/plain"/>
      
  </intent-filter>
  <!-- This activity also handles "SEND" and "SEND_MULTIPLE" with media data -->
  <intent-filter>
    <action android:name="android.intent.action.SEND"/>
    <action android:name="android.intent.action.SEND_MULTIPLE"/>
    <category android:name="android.intent.category.DEFAULT"/>
    <data android:mimeType="application/vnd.google.panorama360+jpg"/>
    <data android:mimeType="image/*"/>
    <data android:mimeType="video/*"/>
  </intent-filter>
</activity>