MoSIP is a SIP based application which is used to make VoIP calls over the internet to any landline or mobile. This cost-effective mobile application can connect worldwide and is suitable for VoIP/SIP providers or other businesses who want to join mobile VoIP market. The advantage of this dialer is it saves money as compared to GSM/GPRS provider. With MoSIP, the users have a facility of "click-to-dial" from contacts and manage calling options such as Hold, Mute, DTMF signal etc, this call gets transmitted over the network of a third party mobile VoIP service provider. The host of operating systems which MoSIP supports are iPhone, Android, Windows, Symbian and Blackberry. This user-friendly application is easy to configure and runs behind NAT and on private IP. Requires either one of the following 2G/3G/4G/Wi-Fi/Edge/GPRS for call connection, as far as low bandwidth is concerned this application operates well in the lowest of lowest signals possible, eliminating the chances of disconnection etc.. When coupled with Vox Bridge, MoSIP works even better giving an exceptional performance over its already existing capability.