MoSIP C5SIP Softphone is a free Android application developed by VOXVALLEY TECHNOLOGIES PTE LTD. It is an enterprise-level UC/IP-PBX softphone designed to bring all the functionalities onto a mobile device, with automated provisioning to manage SIP configurations. This app allows users to stay connected with their business IP PBX phone system from their mobile devices, making it easier to bring out maximum productivity from their workforce. To use the app, users need to configure MoSIP C5 with their enterprise IP PBX system to make it functional.

With MoSIP C5SIP Softphone, users can enjoy voice and video calling, instant messaging & presence, 3-way audio conferencing, and auto-provisioning. The app also supports TLS and SRTP, call transfer, forwarding, waiting & history, built-in echo cancellation, Do Not Disturb, voicemail, multitasking support for incoming calls while using other applications, and Bluetooth accessories support. Additionally, it supports sending of DTMF, G.711 (ulaw, alaw), and G.729.

Overall, MoSIP C5SIP Softphone is an excellent app for enterprises and businesses that require a reliable and efficient softphone to stay connected with their workforce.