Gmail is great on Android tablets.
There might be an overarching desire to not make the Gmail experience too good on the iPad.
There might be an overarching desire to not make the Gmail experience too good on the iPad.
And remember that this is a matter of perspective. The lack of good support for Google services on iOS is a good thing for me - it'll increase the number of people using Android, thus hopefully getting me better Android apps for my phone and tablet.
Apple is the one writing most of the extra code here because they want to make sure Google's services run smoothly on their platform.
While we joke about how crappy it is now, Apple's iTunes for Windows was a good example of playing nice on a competitors platform in an attempt to impress their customers and bring them to your side. It worked.
Gmail isn't great on any Android device. If you have only used Android, it might seem great. But after you try the built-in iOS client, your standards will raise a bit (not intending to offend!).
In my experience, nothing that Google has produced for the mobile platform(s) is great.
A bunch of screen shots included in the link, tablet view as well.
https://play.google.com/store/apps/details?id=com.google.and...
Of course Google has made great things for mobile. Maps are unparalleled. Google Now is fantastic. The Google+ apps are actually fantastic, it's just that no-one is using them.