But what about the style? Google apps all look relatively boring, right? Most of them use the default gray style, and even the ones that don't use very simple variations of darker gray color schemes.
Gray Is the New Black I think that the plain styling of the Google apps is a great thing. Let me explain why. Personally, I very rarely buy any non-black, non-white or non-gray clothes. The simple reason is that I can't be bothered to figure out if a certain tone of red works with my other clothes so I go with the ones that I know always work. I think Google has done the same with the stock app styling. The Google apps will never clash with even the wildest and craziest styles of third-party apps. No matter what crazy apps you install to your phone, the GMail app is always just fine (just like my black shirt).
When Everything Is Gray, Non-Gray Stands OutAnother reason why I think that Google has done us all a favor by staying with their extremely simple styling is that now that we see apps like the amazing Timely, they stand out. Google has left room for third-party apps to shine and stand out.
Making Gray Is EasyThe third thing I really appreciate about the simple styling of GMail, calendar and others is that not every project has a designer (sad but true). On Android, it is perfectly fine to leave your app without styling. The simple, non-clashing coloring and style of the platform lets us, the developer types, use simple math to create our apps. Just make sure that your margins, hit areas and so on follow the design guidelines, and your app visuals are going to be just fine. It'll never win any design contests, but not every app has to.
So, this is why I think Google's apps are awesome: Because they're not awesome.