In 2010, a Russian company Group bought ICQ. In 2016 ICQ changed its design and the new ICQ 10 has been released. Now it looks like Viber. There is a version for Windows, Linux, Mac OS X, Android, IOS, Web and others. Also there is a Java version for other phones.
But only a few people use ICQ nowadays. Because Whatsapp, Skype, Viber, Facebook Messenger are more popular than ICQ. The UIN system is active, I think that it is very good. Now ICQ has video phone calls like Skype, phone calls, and messages, too.