So ideally we would recommend Google's Gmail apps on mobile to complement ours on the computer. We wanted that same approach to extend to the desktop, taking advantage of unique things the desktop environment gives you. We think Google's made pretty decent apps that bring its features to life on tablets and phones, in a way that thoughtfully takes advantage of what the mobile platform has to offer.
We actually envisioned what we were doing from the beginning as a way to complete the Gmail mobile app experience on the desktop.