HTC One M8 - Manual (Page 192)

TalkBack language settings
1. Go to Settings, and then tap Accessibility.
2. Tap Text-to-speech output > Google Text-to-speech Engine, and do one of the
following:
Select a different
language Tap Language.
Install a language Tap Install voice data and tap the language you want.
After the language is downloaded and installed, press
twice, and then tap Language.
3. Select the language you want to use.
Not all languages are supported.
192 Settings and security