The number of QQ accounts connected simultaneously has, at times, exceeded 100 million.[116] While the IM service itself is free, a fee was being charged for mobile messaging as of 2006.[117] Tencent also created QQ International, which is an English version of QQ that allows communication with mainland accounts, QQi is available for Windows and macOS.[118] In 2005, Tencent launched Qzone, a social networking/blogging service integrated within QQ.