One of the coolest features Apple brought to its iPad and iPhone was the pinch-to-zoom gesture, which made zooming in and out intuitive and natural. Previously, zoom controls were either nonexistent or difficult to use. Apple's zoom feature works on photos, web pages, and any app that supports the pinch-to-zoom gesture.
Zoom in on your iPhone or iPad screen with Window Zoom — Apple Support
To zoom in on a photo or web page, press your index finger and thumb on the screen, leaving just a small space between the two fingers. A few things to keep in mind:
You can zoom in and out with two fingers on an iPhone or iPad, but for most people the thumb and index finger work best.
In some cases, the pinch-to-zoom feature won't work. An app might not support the gesture, or a web page might have executing code or a stylesheet setting that prevents the page from expanding.
