I'm using Adobe Acrobat Reader for Android on a Galaxy S5 running on Android 5.0. How can I increase the font size of pdf books without having to scroll back and forth to read the entire sentence.
Also, what to do about pdf articles whose pages are split into two columns other than buying a large tablet.
You can enhance the PDF view experience using the view mode settins. Tap anywhere in the PDF and it will bring a set of tools at the bottom left. Tap on view mode icon at the bottom left and select Text Reflow option. This will reflow the text for better readability. If you want to increase the size more then double tap on the PDF and it will increase the size.
You can also refer to this: Acrobat Reader Help for Android: Set Viewer options