Ask HN: Strategies for marketing android apps and increasing user base

I recently published an app to the google play store called Connect the game. I have had a couple of downloads but no real feedback as to the quality of the app. I believe that I need a larger user base to get the feedback I am looking for, however I have kept the development costs extremely low and don't have a lot of capital to spend on marketing, are there any low cost marketing strategy suggestions that could help increase the user base so that I can get better feedback?

An overview of the game can be found at http://connectthegame.com.