This rumor is a little more complicated than some of the others. Essentially, it appears that Google wants to put the "Ok Google" hotword and/or voice-based actions just about everywhere, with a focus on adding specialized actions for individual apps. This would mean that users could, for example, say "Ok Google" inside the photos app to open a voice box, which would then allow them to perform actions specific to the photo app like sharing, or perhaps starting up the editor.
Google is apparently exploring this idea with new navigation buttons, including a "Google" button that would replace the traditional home button. We'll discuss this further later in the post. Changing the way users access the home screen by implementing a new navigation bar will obviously be a major shift, but we'll explore how that may work in a future post.
Something very important to note right now, though, is that this interface will likely be part of the Google experience, and as such may not appear on non-Nexus/GPE devices. It's clear that Google is trying to build its own experience (with the Google Now launcher being one part) to differentiate its own vanilla Android experience from partners/competitors.
We also have reason to believe that, in some apps, Google is experimenting with functionality that would enable the "Ok Google" prompt to provide suggested actions instead of simply listening. For example, if you were having a conversation with someone in Gmail, the prompt may suggest replying to that person, or performing actions related to the message chain like finding a movie, looking up the hours of a restaurant mentioned in the conversation, etc. This functionality is probably further out, as it would likely require more build-out on Google's predictive/assistive technology, but simpler suggestions like composing an email or creating an appointment are already in exploration (we'll discuss that in a moment).
