Multi-Line SIP SDK

If you are interested in custom multiple line softphone development, you can use our Multi-Line SIP SDK to build a dialer with up to 64 simultaneous lines please use the following form to request a demo.


Development Environments:

  • Visual C++ / C++ / C# .NET
  • VB.NET / VB 6.0
  • Java
  • JavaScript / HTML / HTML5
  • Flash
  • Borland Delphi

Company details:

ABTO Software is the only owner and distributor of VoIP SIP SDK. The company also develops other products and offers software development services. Read more on