FYI - Google just listed their stock calendar app on the PlayStore. Some bugs with HTC phones. Works well on my Sony Xperia Ion LTE.
https://play.google.com/store/apps/...yLDEsImNvbS5nb29nbGUuYW5kcm9pZC5jYWxlbmRhciJd
https://play.google.com/store/apps/...yLDEsImNvbS5nb29nbGUuYW5kcm9pZC5jYWxlbmRhciJd