Image stabilization is also a key feature when recording video, as it helps keep handheld footage steady. The
iPhone 5s supported digital stabilization, and that technology carries through to the iPhone 6. But the iPhone 6 Plus features an optical stabilization system that moves the image sensor to compensate for movement when recording video or capturing still images. The sensor shift system is similar to what Pentax employs in its D-SLR lineup. It allows Apple to implement physical stabilization without having to design a lens with moving elements, which would add size, weight, and complexity to the phone.
Real-World Expectations
Physical stabilization usually nets better results when compared with digital, so iPhone photographers and videographers should give strong consideration to the iPhone 6 Plus. Optical stabilization should improve the sharpness of images in low light (assuming your subject is stationary), and do a better job smoothing handheld video. The Plus's larger physical size and slightly heftier weight will also aid you in holding it steady. It's still too early to make a definitive decision, but based on my experience, I'd say that the iPhone 6 Plus will net better images in challenging light, and smoother handheld video regardless of lighting.