Intent toMain = new Intent(LoginActivity.this, MainActivity.class);
        toMain.putExtra("bool1", "true"); //Optional parameters
        LoginActivity.this.startActivity(toMain);
        //To prevent go back to login
        finish();

Bundle fromLogin = getIntent().getExtras();
if (extras != null) {
    String value = extras.getString("bool1");
    //convert this to boolean
}