iOS: Experimental https://wiki.dlang.org/LDC#iOS_.28iPhone_OS.29

Android: Experimental https://wiki.dlang.org/Build_LDC_for_Android

Windows: Works. Here is the Visual Studio Integration https://github.com/dlang/visuald

Ios kind of works but is lacking bitcode on mobile devices.

Lacking a bit wrapping of system and gui calls but for android see dlangui and Jni is not so bad.

It's very practical to write libraries in D. Possible to write whole apps, but I wouldn't start there for now.

On Windows it's fine, but same library packaging problems as for C++...