We run performance testing using emulators. We verify the acceptability of a server’s performance under unusual and unforeseen conditions. We ensure the performance of the application on various devices with different OS and device configurations. We verify the request and response load at the server-end during multiple user demands on the same resource (i.e. data records, memory). Additionally, we evaluate how applications perform on different networks (2G, 3G, 4G, Wifi, etc.) and during fluctuations among those networks.