Croatian operator Hrvatski Telekom is the first in the country to introduce VoLTE technology, available to users by the end of May. The activation and use of voice services on the HT LTE network is free of charge and the prerequisite for use is the appropriate tariff, a device that supports VoLTE and the appropriate software version. The first devices in HT's portfolio with VoLTE support are the Samsung Galaxy S7 and Samsung Galaxy S7+, while other manufacturers will soon be available.
Source: https://www.telecompaper.com/news/hrvatski-telekom-first-in-croatia-to-introduce-volte--1197557
