Hmm...difficult to tell. Personally, i don't like ads so i did not include them in the app. However, at some point I do agree it needs to make some money in order to be sustainable. I'm not sure about the right approach here, but if userbase continue to grow to a point I could no longer support, I will definitely open a discussion about possible approaches, with ads being one of them. In a good tradition of gridcoin, I think community should decide.