What is the fine-grained topic of the following text: Japanese carrier DoCoMo released the new Galaxy S4 variant for the Japanese market and there’s no word yet on whether it will be available outside the Asian nation in other markets like the North American market, the European market or whether we’ll see the international version of the S4 also get a blue coloured brother. Only return the topic.
Release of new Galaxy S4 variant by DoCoMo in Japan