Samsung talkback text to speech engine is not allowing to completely delete some voices like-Vietnamese (Vietnam voice. After deleting from apps it still shows in Samsung TTS setting.
Indian languages are only available in one voices, quality of clearity and accent is very bad even with the Indian english voice and Indian languages voices update come rarely.
It does not have third party TTS support unlike Apple's Voice over has Aloquence, Vocalizer and Espeak engine.
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