Google would appear to be preparing to pull the switch and earn itself an even bigger chunk of money from Android, with code inside its updated Gmail app referencing layouts and systems for incorporating advertising within the mobile messaging tool.
Version 4.6 of the Android Gmail app that arrived on phones last week contains stacks of design references allowing for ads to be included inside the email app, so they're definitely coming, although it's impossible to tell at this stage what format the ads might and how they'll be formatted. We'll find out whenever Google grits its collective teeth and makes them live.
Interestingly, the code hints that there will be a option to save or archive ads as if they were proper emails, should you see one you like and want to keep. We can't imagine anyone, ever, doing that. [Android Police]