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It's about as practical as any other language these days, it runs on practically any computer or phone you might want, and you can use the internet to share applications to anyone with a browser. (No downloads, no installs.)
(Note: I'm collaborating on a general permutation puzzle simulation library at https://github.com/cubing/kpuzzle.js which might serve your purpose, but it's still rough around the edges.)
JavaScript, C#, or Swift is what I'd recommend. If you're not planning to develop for a mobile device (excluding responsive design), I'd go with JavaScript.
Swift is for Apple only, and C# is universal for the most part with some minor tweaks for different OS.
Realistically you can use just about any language you want with some extra libraries/packages and work.