If Android device manufacturers want to include Google apps and services on their products, they must adhere to a set of requirements laid out by Google. One of these requirements is that OEMs must pre-install a range of Google applications on their devices, some of which are useful to pretty much all users, and some of which are not.
The inclusion of a handful of apps that aren't used by everyone sometimes makes Android devices feel like they're loaded up with bloatware. Google has recognized this fact, so the company has shortened the list of apps that must be pre-installed on Android devices with Google services.
This means that OEMs no longer have to pre-install four applications: Google+, Play Games, Play Books, and Play Newsstand. Some manufacturers might still decide to pre-load these apps on their devices, but many will choose not to. Samsung, for example, has already taken advantage of these new rules by choosing not to pre-install Google+ on the Galaxy Note 5.
The four apps that no longer need to be pre-installed are some of the least-used from Google's mandatory package. For those that want to continue to use these apps, they will still be available in the Google Play Store and will be regularly updated by Google, just like some of their other apps such as Keep, Earth, Fit, Inbox and Cardboard.
OEMs will still be required to install crucial apps such as Gmail, Maps, Google Search, Chrome and the Play Store. Other more optional apps will continue to be pre-installed, including YouTube, Play Music, Play Movies, Play Books, Drive, Photos and Hangouts.