Anyhow, the Android Design guide is insightful and inspiring. In the "Design Principles" section, it has three main categories - "Enchant Me" - "Simplify My Life" - "Make Me Amazing" - and in each case, "me" is the person holding the phone and there are subcategories for each that give specific examples of the types of interactions that best exemplify those traits.
But one thing struck me... there's a bunch of time spent on where to place buttons, how they should look and act, and even a section admonishing the developer not to get lazy and just make an app for Android, Apple iOS and Windows Phone 7 (yeah, I've never heard of that either), but to take care to use the conventions of Android for Android apps so you don't confuse or alienate your users.
Apparently, that advice doesn't apply to them. Google offers up a Gmail app on iOS. It offers you access to some of the Googlely goodness of Gmail that the built in iOS Mail app can't offer. But it's supremely ugly. And clunky. And different from any other professional apps on the iPhone.
And yet, to read this guide, it sounds like it's following most of the Android conventions and I suspect to use the app on Android, it would feel beautiful, fluid, consistent. That this isn't a problem with the app, per se, it's a problem with the guys who built it not following the advice of their colleagues - that the Gmail app for iPhone isn't designed with the iPhone in mind. That it's simply a copy of the Android version with Android's purposefully non-3D, non-rounded, dark, low-resolution icons and menu placements.
In the same way that you must spend several seconds on each new website unconsciously learning the conventions of their menus (why most websites adopt the top and left navigation structure and why IMDB is so frustrating), there's a "switching cost" each time you move from app to app that doesn't follow convention.
And the Gmail app certainly does not follow iPhone convention and therefore there's a negative association immediately upon first use because even if it's supremely powerful (it is) and offers you access to all kinds of features the built-in version doesn't (it does), the fact that it forces you to change your way of thinking immediately gives it a negative switching cost.
Perhaps that's why it only has 3-stars.f