ExoLens with Optics by ZEISS iPhone Accessory
With each new iPhone, Apple improves the camera. Some say the iPhone 7 and 7 Plus incorporate the best iPhone camera yet, with 12 megapixels, optical image stabilization, an f/1.8 aperture that pulls up to 50 percent more natural light (compared to an iPhone 6s) onto the sensor to enhance low-light photography; and a "quad-LED" flash with four LEDS to create a flash that's 50 percent brighter than the iPhone 6s's flash.
The iPhone 7 Plus includes two rear-facing lenses instead of the usual single lens, which lets you use the lens to zoom in on a subject vs. zooming via software, which degenerates image quality.
One other iPhone 7 camera feature worth mentioning: a 7-megapixel front-facing (aka selfie) camera vs. the 5 megapixel cameras in the iPhone 6s and 6s Plus smartphones.
OK, now that you know what you're missing, you should also know about the plethora of camera lens add-ons for iPhones. Among the best is the ExoLens with Optics by ZEISS (a well-respected lens maker), a camera attachment available foriPhone 6 and 6s and iPhone 6 Plus and 6s Plus, both of which cost $200.
The ExoLens with Optics by ZEISS is a wide-angle lens that's the equivalent of 18mm, which can help you capture a wider landscape, group shot, or other image, vs. the iPhone 7's 28mm-equivalent lens and the iPhone 6/6s model's 29mm.