Changing language settings in an IPTV player
An IPTV player's app language (menus and buttons) is separate from the language of your content or subtitles — you set those independently through settings.
App language vs content language
The app's own language (for example Dutch, English, German, French or Spanish) only determines how menus and buttons are displayed. It has no effect on which audio or subtitle languages are available for a specific movie or show — that depends on what your playlist provider supplies, or what you download yourself.
Changing the app language
This is usually done via a language picker in the settings menu, or directly on the login/home screen, with one click per language.
Why this is kept separate
This lets you, for example, use the app in English while watching movies in Spanish with English subtitles — the three settings (app language, audio, subtitles) are entirely independent of each other.
