The indoor positioning system (IPS) is a significant factor to develop many applications such as direction and navigation in large commercial centers, tracking valuable goods, or determining position of children or old people. With the rapid growth of Internet, Wi-Fi access points (APs) can be found almost everywhere. This widespread infrastructure offers the possibility to locate mobile devices in an economical way. Therefore, Wi-Fi based positioning systems have become an attractive positioning technology in urban areas where GPS signals can be weaker, or where the use of GPS puts too much strain on the device's battery [1]. In order to enhance accuracy and stability of the Wi-Fi based positioning system, we proposed a robust, ubiquitous, and precise indoor positioning solution for smart mobile devices based-on the combination of Wi-Fi positioning system and embedded sensors on the smart devices.The new method will be analyzed and tested in real experiments.Experiment results have shown that our method can provide better accuracy to compare with traditional methods.