There’s a particularly interesting new Accessibility setting in iOS 10 that lets you put a magnifying glass in your pocket. The feature uses the iPhone’s camera to magnify objects and reaches beyond what the zoom inside the native camera app is capable of for even more magnification.
The feature can be enabled by going into Settings -> General -> Accessibility -> Magnifier and toggling it on.
After that, all you need to do is triple-click your home button from any screen to bring up the Magnifier app. A slider adjusts the magnification effect and while the center button looks like the same one inside the native camera app, it only freezes the image until you press it again — nothing is actually saved. The familiar lightning bolt icon turns on the camera’s flash as a steady light source.
The icon on the lower right is familiar too but instead of adding photo filters, it adjusts the brightness and contrast and triggers multi-color modes, likely a feature added to assist with colorblindness.