At the top of the post it says it's open-source, and at the bottom of the post it says it is closed-source.
Can I ask why you are selling this instead of developing it further? Would you be interested in bringing on another developer?
i wrote that i want to sell the google play rights over the published app, so you can gain the right to manage the already published app, deploying updates, introducing features.. it has already ~400 users. If you don't like to buy the rights you can publish your own app using my source code (if you like the code, obviously)
Why i'm selling it? Because i'm not interested anymore on developing this app.. maybe if you want you can submit a pull request and i can merge your improvements with my code base and than deploy the updates on Google Play.. but i'd prefer to sell it to let another maintainer getting the job done in the right way.