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While the free Zoiper Community Edition is functional with Sharpen across the Windows, MacOS, and Linux operating systems, we do not endorse its use outside of testing.
If running for perpetual commercial use, you should purchase the product and understand the tool will not be supported by Sharpen.
If you’re only running the Windows operating system, an open source alternative, MicroSIP, might be a suitable option as well; often preferred for its lightweight, streamlined interface.
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