Microsoft Edge is currently available for Windows 10 devices only. As for Windows 10 mobile devices, it will be the only browser. For other Windows 10 devices like laptops, desktops, tablets etc, it will be available along with Internet Explorer.
Microsoft has not revealed any plans to make the browser available for other operating systems. As such, it is not available for other operating systems than Windows. It may be available in future, but Microsoft has concentrated on developing it for Windows operating system.
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