Due to the increasing demand for data transmission anytime and anywhere, the low bandwidth and high jitter of the communication of a single heterogeneous wireless network seriously affect users’ experience of mobile devices. Considering the actual demand of mobile devices for link aggregation of heterogeneous wireless networks, especially the demand of Android mobile devices, this study proposes a scheme to realize link aggregation of mobile data networks and WiFi networks, two heterogeneous wireless networks, on mobile devices. The scheme is based on the application layer development, which skips the complex packet encapsulation process of the lower layer and does not change the hardware configuration of a mobile device. In this study, the working principle and design idea of wireless link aggregation are described, and the program is implemented and tested on Android phones. The test results show that the aggregation scheme of heterogeneous wireless links can significantly improve network bandwidth and file transfer speed.