Iskratel x10

Unified Communications VoIP client

Iskratel is a leading European provider of communications solutions for the digital transformation of the telecommunications, transport, public safety, and energy industries.

What we've built?

Kalmia and Iskratel have joined their forces to develop a multi-platform unified communications VoIP client which is tightly coupled with existing Iskratel UC solution and offers advanced services with numerous business features. UC provides true fixed-mobile convergence with single identity regardless of device or network.

VoIP protocols and standards

In this project, we brought to the table our deep know-how in VoIP protocols (SIP(S), RTP(S), MSRP, XCAP…) and standards (VoIP, RCS, IMS). We proposed practical solutions to the problems with a strong awareness for scalability and interoperability.


When defining UI we tried to follow the rule of the consistent UX no matter of the platform behind (Windows, Android or iOS). Another strong commitment was modularity of the application which is automatically provisioned and presents various features depending on the user license. UI is modern but still suitable for everyday use within a business environment.


Applications were developed in C# (Windows), Java (Android) and Objective C / SWIFT (iOS). Open source C++ SIP stack is used under the hood. It is linked to the presentation layer via individual wrappers. All applications provide crash and usage analytics and are automatically built and deployed (to Google Play and Apple Store) by Jenkins continuous integration tool.


  • AndroidAndroid
  • iOSiOS
  • WindowsWindows
  • FastlaneFastlane
  • PrismPrism
  • SIP/RTP StackSIP/RTP Stack
  • JenkinsJenkins