Localisation and then some


I’m teaching myself android programming to create data collection tools for use by a group of First Nations on the B.C. coast. It would be really cool if in, say, a list of species (eventually, once I get to that point…) I could have the English names and then FN translations into say Kwa’kwala or S’malgyax. But the built-in Android localisations probably won’t work for that, since those aren’t options at the OS level (and even if they were, users may not want their entire phone OS’s localised). Any suggestions on how to even approach thinking about a localisation that’s more within the app than set by the OS? Or should I/ is it possible to create new languages for the OS to offer as options, which would default to an existing language (en-canada, say) for anything that doesn’t recognise the new one?