Yesterday I submitted my Dave Dangerous game to the Amazon app store. I have made a small change to use Amazon's own ad service. I have found that the fill rate was not great, only 20% of ads served, so Admob will be used as a backup.
If you have a Kindle Fire, please download it here: https://www.amazon.co.uk/dp/B01GQ6ODMC
I'll get my next game published to Amazon Underground.