In the past several years, there have been dramatic changes on the Web services landscape．After the traditional XML-PC web service, a new style-Representati0nal State Transfer (REST) is applied to Web services. In addition, the telecom operators have provided different APIs. OneAPI standards have been proposed. This article mainly introduces OneAPI standards and REST architecture. Some OneAPI supplied by GSMA website to provide REST service. Sample program implements can get the user address though the OneAPI.