Several usages of Android Intent are explained in detail

Intent is kind of unique to Android. You can specify in Intent the action to be performed by the program (e.g., view,edit,dial) and the information the program needs to perform the action. Once you've specified everything, just call startActivity(), and the Android system will automatically find the application that best fits your requirements and execute it.

Here is a list of several USES of Intent
Display page:

Uri uri = Uri.parse("http://www.google.com");
Intent it  = new Intent(Intent.ACTION_VIEW,uri);
startActivity(it);

Display map:

Uri uri = Uri.parse("geo:38.899533,-77.036476");
Intent it = new Intent(Intent.Action_VIEW,uri);
startActivity(it);

Path planning:

Uri uri = Uri.parse("http://maps.google.com/maps?f=d&saddr=startLat%20startLng&daddr=endLat%20endLng&hl=en");
Intent it = new Intent(Intent.ACTION_VIEW,URI);
startActivity(it);

Telephone:
Call dialer

Uri uri = Uri.parse("tel:xxxxxx");
Intent it = new Intent(Intent.ACTION_DIAL, uri);  
startActivity(it);  
Uri uri = Uri.parse("tel.xxxxxx");
Intent it =new Intent(Intent.ACTION_CALL,uri);

To use this you must include it in the configuration file < uses-permission id="android.permission.CALL_PHONE" / >
Send SMS/MMS
Call the program that sends SMS messages

Intent it = new Intent(Intent.ACTION_VIEW);   
it.putExtra("sms_body", "The SMS text");   
it.setType("vnd.android-dir/mms-sms");   
startActivity(it);  

Send a text message

Uri uri = Uri.parse("smsto:0800000123");   
Intent it = new Intent(Intent.ACTION_SENDTO, uri);   
it.putExtra("sms_body", "The SMS text");   
startActivity(it);  

Send MMS

Uri uri = Uri.parse("content://media/external/images/media/23");   
Intent it = new Intent(Intent.ACTION_SEND);   
it.putExtra("sms_body", "some text");   
it.putExtra(Intent.EXTRA_STREAM, uri);   
it.setType("image/png");   
startActivity(it);

Send Email

Uri uri = Uri.parse("mailto:xxx@abc.com");
Intent it = new Intent(Intent.ACTION_SENDTO, uri);
startActivity(it);
Intent it = new Intent(Intent.ACTION_SEND);   
it.putExtra(Intent.EXTRA_EMAIL, "me@abc.com");   
it.putExtra(Intent.EXTRA_TEXT, "The email body text");   
it.setType("text/plain");   
startActivity(Intent.createChooser(it, "Choose Email Client"));  
Intent it=new Intent(Intent.ACTION_SEND);     
String[] tos={"me@abc.com"};     
String[] ccs={"you@abc.com"};     
it.putExtra(Intent.EXTRA_EMAIL, tos);     
it.putExtra(Intent.EXTRA_CC, ccs);     
it.putExtra(Intent.EXTRA_TEXT, "The email body text");     
it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");     
it.setType("message/rfc822");     
startActivity(Intent.createChooser(it, "Choose Email Client"));  

Add attachments

Intent it = new Intent(Intent.ACTION_SEND);   
it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");   
it.putExtra(Intent.EXTRA_STREAM, "file:///sdcard/mysong.mp3");   
sendIntent.setType("audio/mp3");   
startActivity(Intent.createChooser(it, "Choose Email Client"));

Broadcast multimedia

  
Intent it = new Intent(Intent.ACTION_VIEW);
Uri uri = Uri.parse("file:///sdcard/song.mp3");
it.setDataAndType(uri, "audio/mp3");
startActivity(it);
Uri uri = Uri.withAppendedPath(MediaStore.Audio.Media.INTERNAL_CONTENT_URI, "1");   
Intent it = new Intent(Intent.ACTION_VIEW, uri);   
startActivity(it);  

Uninstall program

Uri uri = Uri.parse("geo:38.899533,-77.036476");
Intent it = new Intent(Intent.Action_VIEW,uri);
startActivity(it);

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