I really wanted to expand my vocabulary in Latin, but I only study it through Duolingo. So I had an idea of implementing it as my phone language! (I've done it with English, and the results were, well, pretty good)
However, as I expected, no 'Latin' language pack comes up.
Is there any way to implement this on PC or Android phones...?
The closest to a general Latin interface (that I've ever seen) is using Google translate, and maybe you could try Google Voice on your phone--I don't know about that. But DON'T DO IT. So far, Google's Latin translations are so wrong so often that they are worthless, and the voice "recognition" is actually simply Italian voice recognition.
You will just have to try something other than Duo to advance past what Duo offers, or wait until the course is expanded. You'll of course make much quicker progress if you don't wait for a course expansion. There are plenty of options for continuing with Latin besides Duo.
Latin is not a dead language, it's still living, and technology words are translated in Latin.
Of course, it's not the same Latin than Cicero, but neo-neo-Latin, but the grammar should be theoretically similar.