Free trial period is not limited, you can use SDK as long as you need.
During the trial, you'll have full access to all features of the SDK, with just one exception: call duration is limited to 60 seconds.
Upgrading to a paid license removes this restriction, enabling calls of any length.
Single license allows to use SDK in an unlimited number of applications and computers/devices.
See more: How to purchase SDK
Ready to use examples applications with source code:
Dart Flutter (Android/iOS/Windows/MacOS/Linux) FlutterPlugin
C# WPF (Windows) - SampleWPF
C++ Console app (Windows/MacOS/Linux) - SiprixUA
Java (Android) - SampleJava
Swift (iOS) SampleSwiftUI
C# MAUI (Android/iOS/Windows) - SampleMAUI
SIPRIX doesn't provide VoIP services, but in the same time doesn't have back-end limitations and can connect to any SIP (Servers) PBXs or make direct calls between clients.
Use these archives for updating SDK in the existing project.