Android - Download a folder from server or anywhere from internet and apply changes according to it in app
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I just finished one app, but i want to let user install different language packs (a folder containing mp3 files ), and also apply those mp3 files in my app ! how should i do it ?
how to let user user download that folder ?
and how to make changes in my app as they download ?

(this is like google maps app, they tell you which map you want to install and so on ! mine is related to mp3 files ! )