We are using Google's Messenger app and have not loaded our own SMS/messaging app. As such, we can pass your feedback to Google as a general request - but changing the app and its functionality is outside of our control.
As to the decision whether or not we should pre-install and develop our own ASUS SMS app, we are so far deciding against this - as we want to stay close to stock Android and add function where we see it best being used instead of everywhere for the sake of changing it.
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