Thực đơn
FreemiumThực đơn
FreemiumLiên quan
Tài liệu tham khảo
WikiPedia: Freemium http://www.pocketgamer.biz/feature/57185/i-wrote-f... http://money.cnn.com/magazines/business2/business2... http://www.entrepreneur.com/article/218107 http://uk.gamespot.com/news/ea-freemium-is-where-t... http://gigaom.com/2011/03/10/apple-now-requires-pa... http://abcnews.go.com/blogs/technology/2012/04/par... http://www.mmorpg.com/discussion2.cfm/post/5512465... http://www.polygon.com/2014/11/21/7258763/valve-st... http://www.techstarthub.com/2011/09/11/freemium-ap... http://www.cjr.org/the_audit/the_nyt_paywall_is_ou...