Android open emailclient programmatically

Yes. You can launch it via Intents.

Intent i = new Intent(Intent.ACTION_SEND);
i.putExtra(android.content.Intent.EXTRA_EMAIL, new String[]{ emailAddress });
i.putExtra(android.content.Intent.EXTRA_SUBJECT, subject);
i.putExtra(android.content.Intent.EXTRA_TEXT, text);
startActivity(Intent.createChooser(i, "Send email"));

Intent i = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(
                    "mailto", EMAIL_ADDRESS, null));

up to date way of doing it

        i.putExtra(android.content.Intent.EXTRA_SUBJECT, SUBJECT);
        i.putExtra(android.content.Intent.EXTRA_TEXT, BODY);
        startActivity(Intent.createChooser(i, "Send email"));