Zoom 
To use this feature, tap Zoom and choose one of the following options:
- Fit
- Fit width
- Actual size
Text-To-speech 
Text-to-speech is offered in a range of languages. To begin, select the appropriate language and MobiPDF will automatically read the text aloud for you, starting from the beginning of the document.
For even greater control, scroll to the bottom of the language list and tap More options. From there, you can set your preferred speech engine, speech rate, and voice pitch.
Dark mode
Enable Dark mode from the View Settings menu to darken the white background of your documents and reduce eye strain.
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