When displaying a PDF or EPUB file on a mobile device, you can use the standard pinch-and-zoom feature, making a page larger or smaller by pinching or spreading it with two fingers.
On a web browser, use the short cut of CTRL + to zoom in and CTRL – to zoom out.
READynamic offers a pen feature that is available as a menu option when reading an eBook. A user can use this feature with a browser if that browser is touch sensitive, allowing for a pen or stylus, like Microsoft Edge. For these browsers, including recent versions of Internet Explorer and Mozilla Firefox, you can zoom in by tapping the screen. But an error in the browser software prevents this feature from working with an READynamic reader using Google Chrome.