Just because you didn't attend Google I/O, you don't have to miss out on some of the helpful education from Googlers. The company has posted a plethora of developer sessions online for you to watch any time you want. Even if you did attend, you couldn't have gone to all of the sessions, and you might want to re-watch some of those you did attend.
Android developers should be interested in this one, designed to help gain exposure to apps in the Google Play store.
"As soon as you hit the 'Publish' button on your app, you become (partly) a marketer; you might as well try to be a good one," Google says in the description. "We'll share everything we know about promoting apps on Google play: building a strategic marketing framework, making good use of media channels, taking advantage of the assets we've built for developers, and convincing the Play team to feature your app."