John Gruber - Google’s App Aesthetic

To me, they look and feel like Android apps running on iOS. Android users might disagree with that assessment, as much of what makes a good Android app Android-y is not how the software looks but the way it interacts with the system. But these Google apps certainly don’t look or feel quite like iOS apps.

This 100%. I use Google for my calendar and email, but can't use their iOS apps because they break all the expectations of iOS. Personally, I think it would go a long way if they would just support the standard share sheet in iOS8.