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Although originally designed for simple voice communications, most modern telephones have many additional capabilities.[http://dichvuvanchuyen.com.vn/dich-vu/chuyen-nha-tron-goi/chuyen-nha-tron-goi.aspx chuyen nha tron goi]  They may be able to record spoken messages, send and receive text messages, take and display photographs or video, play music, and surf the Internet. A current trend is phones that integrate all mobile communication and computing needs; these are called smartphones. [http://dichvuvanchuyen.com.vn/dich-vu/chuyen-van-phong/chuyen-van-phong.aspx chuyen van phong]