Yes! We do support regional dialects.
If you want your app to be translated in Portugal (PT) as well as Brasil (PT-BR) you should add both languages to the Applanga dashboard.
If an app requests a dialect (e.g. PT-BR) the SDK will first check if there are translations in that language-dialect (PT-BR) but if a string is empty or the dialect does not exist it will fall back to the superordinated language (PT). If the string is empty there as well it will fall back to the base language.
If you only create and translate the regional dialect (eg. PT-BR) and not the original language (eg. PT), only users with their phone set to the region will get the translation. Everybody else that is requesting the original language or another regional dialect will get the Base Language localization.