China Unicom (stock code: 600050) subsidiary Guangdong Unicom partnered with China Southern Airlines to release SMS-based flight inquiry service on January 31, reports Sina. The service allows users to send SMS messages containing their China Southern flight numbers to one of two designated numbers in order to receive an SMS reply containing flight departure and arrival times. According to the report, the service will be available to China Unicom users nationwide. The service is currently limited to Guangzhou Unicom users taking China Southern flights through Guangzhou, according to a China Southern customer service representative.