Question

I need to receive sms from this a particular number, encrypt it and later sent in the inbox. This way my message is protected from reading by anyone else who handles my phone.

Answer 1

Try something like this

ContentValues values = new ContentValues();
values.put("address", "123456789");
values.put("body", "foo bar");
getContentResolver().insert(Uri.parse("content://sms/inbox"), values);

I hope this helps