ZarpVoip Dialer is a mobile app for VoIP platform that works as a terminal for making VoIP calls. It utilises SIP protocol and requires data service of GPRS/3G/4G or WiFi network. This application is designed for VoIP service providers and end users. Service providers should provide their soft switch IP and port and they will get an operator code for their service. Customizable branded solution also provided for service providers. End user requires operator code, user name and password provided from service provider. Features: 1. VoIP incoming and outgoing call via GPRS/3G/4G or WiFi data service2. Supported codec: G. 729, G. 7113. Support full functional SIP to SIP call with local and remote ring back tone4. Works behind NAT5. Can bypass any Firewall6. Low bandwidth consumption by customized byte saver solution7. Can bypass SIP blockage8. Smart echo cancellation technique9. Synchronization with phone contact10. On screen call time display11. On screen balance display12. Call log of incoming and outgoing calls and, can make call from that log13. DTMF support (RFC 2833, SIP Info) 14. PLC (Packet Loss Concealment) and VAD (Voice Activity Detection) implemented15. Works with or without byte saver solution16. Alert system by local Inbox message or pop-up message17. User panel with login details for service providers. Service providers can see from which country and mobile operator (for GPRS/3G) users are registered18. Single customizable solution based on different mobile network/data service.