Change the language from app?

Phone-level language control is typically done using restricted interfaces: as far as I am aware there is no direct control from an app as part of the public Android interface.

Your best bet would be to use an Intent to open up the language picker. The Intent filter is:

<intent-filter> <action android:name="android.intent.action.MAIN" /> <action android:name="android.settings.LOCALE_SETTINGS" /> <category android:name="android.intent.category.DEFAULT" /> <category android:name="android.intent.category.VOICE_LAUNCH" /> </intent-filter> 

So something like this should work:

Intent i = new Intent(); i.setAction(android.provider.Settings.ACTION_LOCALE_SETTINGS); i.addCategory(Intent.CATEGORY_DEFAULT); i.startActivity(); 

And then the user can pick their language from there.