although you can put ads. If your crowd is technology minded they won't work, as they will likely have adblockers installed. But people are used to ads and as l

although you can put ads. If your crowd is technology minded they won't work, as they will likely have adblockers installed. But people are used to ads and as long as they aren't obnoxious people will be unlikely to complain. But more carrot than stick. If you hit your users with a stick too hard they won't want to pay and will leave, they may even talk to other users who wouldn't have cared and convince them to leave. Perks are good. If you have any kind of social aspect consider having people advertised as paying. Theres a certain... prestige gained by letting people know that you are paying for a product that can be mostly used for free (at least I think there is).