Well, for starters I do not host any files on my server. That alone I think could help keep my server costs way down 🙂
Also, in the future I’m going to try to make notification syncing not go through my server at all if possible. That will bring the costs way down since that is the most activity I have on my server right now, by far.
Also, I already have some recurring revenue options in place: people can support the app/server after they unlock it so I can keep it running and they can also keep ads enabled to help out even further.
From what I can tell it seems it’ll be sustainable 🙂