UPDATE: Also get users to recommend your app via Google+
In order to increase the number of engaged users who were rating the Android version of Word Crank, we used a small piece of code from Android Snippets that shows a dialog to the user after a number of predefined uses to rate your Application. What were the results?
There were 0.2 App Ratings/day previous to adding the App Rater Dialog, after adding the App Rater dialog we went to 0.33 App Ratings/day. That is equivalent to a 65% increase in user app ratings by making such a small change. We felt that this was an important change as user ratings can help increase your placement in the Android Market. Also, we were hoping to get more positive ratings as the dialog only appears after a user has played the game at least 3 times.
So why not give it a try in your game? Let us know your results in the comments below.